The first civilization in human history was that of the Sumerians. This emerged in the mid-4th millennium BCE, with the appearance of the first cities on the Mesopotamian flood plain. This was a pivotal event for mankind – but why here? And why now?
The Rise of Farming in Mesopotamia
By 6000 BCE, farming settlements dotted the Middle Eastern landscape from Egypt to Iran. Most of these were small villages, but some, like Jericho, were sizable towns. Jericho, situated in a large oasis, consisted of 8 to10 acres of mud-brick homes surrounded by substantial walls. Large water tanks were probably used for irrigation, and a massive stone tower for defense. It had a population of some 2,500 people.
The farming population in the Middle East was distributed across the “Fertile Crescent”, that huge stretch of territory from Egypt in the west to Iran in the east were farming is easy and productive. One region where farming was not yet present, however, was southern Mesopotamia. This low-lying plain was too dry to allow farming; there simply was not enough rain, apart from during a very brief period in the spring, to grow crops.
In about 6000 BCE, irrigation began to be practiced in the foothills of the Zagros mountains, very near southern Mesopotamia. Communities of farmers dug tanks and reservoirs to store water, and ditches to lead it to the fields throughout the growing season. In this way they were able to water their fields over a long period of time, increasing their yield of crops.
The techniques learnt here enabled farmers to settle in the dry southern Mesopotamian plains. By creating irrigation systems, they were able to feed their crops with water well beyond the brief rainy season.
The farming villages faced a further challenge, however. This region has no mineral resources to speak of, so the new communities had to import all their stone – for tools, decorations and weapons – from elsewhere.
Trade networks can be traced far back into pre-history, before agriculture in fact. Hunter-gatherer sites 100 miles inland show stores of shellfish which must have come from the coast. The spread of agriculture, however, would have greatly stimulated trade.
One of the beneficial characteristics of cereal staples such as wheat and barley is that they can be stored for a long time before eating, unlike fruit, berries and meat. Buildings for communal grain storage are a universal feature of early farming villages, and they will have been able to build up food surpluses. This in turn will have allowed them to survive periods of drought as well as use grain for trade with neighboring peoples. Trade routes gradually developed over long distances. These would almost certainly not have been operated by long-distance traders, but rather have grown up through repeated local exchanges. Bladed tools of obsidian, a semi-precious stone found in Asia Minor, have been discovered in south western Iran dating from as early as 8000 BCE.
Returning to the period just after 6000 BCE, then, and to those new communities in the dry and mineral-poor plain of southern Mesopotamia, they were able to survive only by creating irrigation systems and tapping into the already-existing trade routes of the region. Having survived, however, they thrived. The plains of southern Mesopotamia have wonderfully rich soils, deposited by the rivers Tigris and Euphrates over thousands of years. Watered by means of irrigation, they turned into highly productive farm land, able to sustain large populations.
Archaeology traces the growth of these early southern Mesopotamian communities from just after 6000 BCE down to historic times, and witnesses their growth from farming villages into the first true cities in history, two and a half thousand years later.
This comparatively sudden growth of a dense new population in the Middle East must by itself have quickened trade in the region. The two thousand years between 6000 BCE and 4000 BCE saw a very large expansion of population in southern Mesopotamia. The pace of change quickened, with new inventions appearing. Most notable, the wheel had arrived by 4000 BCE, and a few hundred years later they were being fixed to ox carts.
Ancient Mesopotamian cylinder seal
Reproduced under Creative Commons 3.0
They were also being used by pottery makers – and indeed the potter’s wheel is a pointer to the appearance of craftsmen making artifacts for a wide market. The artistic standard of pots in fact declines with the advent of this device, as for the first time potters churn out their wares quickly and cheaply. This is a clear sign of the increasing trade of the region.
Within southern Mesopotamia itself, the archaeological record indicates that over the course of hundreds of year, the Tigris and Euphrates plain became ever more thickly studded with farming villages. Some of these became religious centers, each home to a small temple of a local god which the people of the surrounding villages worshipped. It was these centers which later evolved into the Sumerian city-states of later centuries.
How exactly this happened is of course unknown. One likely scenario is that, as the population grew and the available land came under the plough, disputes arose between villages as to land- and water-rights. To resolve these disputes they turned more and more to the local temple, with its (at that time small) group of priests, whose religious prestige thus gradually evolved into a judicial authority covering a locality.
This authority was further augmented by the need to build large-scale dykes and canals to contain the flooding of the turbulent rivers; this would have involved the labor of men from a whole locality, not just one village, who would need to be controlled as a body. Furthermore, as groups of villages were co-ordinated into tighter co-operative, even “political”, units, conflict would now involve locality against locality. Individual villages would have been very vulnerable in these circumstances, and the trend would all have been towards greater power shifting to the temple priests, now transformed into something like a ruling class.
An Urban Revolution
The archaeological evidence would harmonize with this narrative, as it shows the gradual enlargement of these temple centers surrounded by many villages. This was the situation by about 4000 BCE. Over the following few centuries, however, the temple centers – and indeed the temples themselves – grew massively.
Sizable towns appear, and by 3500 BCE several are true cities with tens of thousands of inhabitants. The largest, Uruk, may have been home to 40,000 people. This development was accompanied by the decline in the number of small villages. Clearly a concentration of the population within the city precincts was taking place, very likely for protection.
This dramatic development has been called an “urban revolution”, and it reflects in physical settlement patterns the transformation of society into a much more complex organism than any up to this time. The large surpluses made possible by the rich soil of the plains had come under the control of religious and political elites, centered on the temples. By imposing tribute and taxes on the surrounding population, these had accumulated wealth on a scale undreamt of in previous times.
This they used to construct monumental public buildings – granaries, temples and palaces. These overawed the people and proclaimed their power, and indeed helped to reinforce it. The granaries were centers of a distributive system whereby the temple officials controlled much of the economic life of the people. The god (and therefore his temple) was held to own the land and people of the state (which the locality can now fairly be called); and this translated into the temple elite directly controlling much of the land and labor of the city and its surrounding area.
Much of this wealth was devoted to the decorative arts, and along with a ruling group a class of full-time professional craftsmen emerged. The standard of craftsmanship – indeed, of representational art – was raised to new heights. This was not only stimulated by the desire to decorate temples and other public spaces, but also to manufacture trade goods needed to keep the inward flow of raw materials, in which southern Mesopotamia was so sadly lacking, open. This in turn stimulated long-distance commerce.
A final development needs to be noted, perhaps the most important of all. The demands of administering land and wealth on a scale hitherto unknown presented significance challenges to the temple officials. To meet this challenge, they developed a system of symbols to record the huge number of economic transactions they were overseeing. From these early foundations writing scripts evolved, and the first literate societies appeared.
The period after 3500 BCE saw the world’s first civilization, that of the Sumerians, reach a peak of cultural dynamism as their small city-states competed with one another for dominance.
Early Sumerian Advances
The period after 3500 BCE is known to historians as the Early Dynastic period of Mesopotamian history. It saw Sumerian civilization increase in complexity and sophistication. In particular, writing made important advances. From the early pictograms, the script gradually became more abstract and stylized. It also became more linear, reflecting the use of the wedge-shaped styluses used to inscribe the clay tablets.
By around 2500 BCE the script had developed into classic Sumerian cuneiform writing, with which a subtle and varied literature, containing economic and administrative documents, letters, stories, prayers, hymns and so on was being committed to writing.
Sumerian inscription on a creamy stone plaque,
9,2×9,2×1,2 cm, 6+6 columns,120 compartments of archaic monumental cuneiform script
The urbanization process reached its peak in the early 3rd millennium, and spread throughout the whole of Mesopotamia and beyond. In northern Mesopotamia cities appeared at places like Mari and Assur, and other cities appeared in Elam, Syria and eastern Turkey. The people of these cities were influenced to a great extent by Sumerian art and architecture; colonies of Sumerian merchants were established in some centers, though more local influences were also apparent.
The eighteen recorded Sumerian cities of southern Mesopotamia remained concentrated along the branches and irrigation canals of the Euphrates in a narrow strip of land extending from south of present-day Baghdad to the marches bordering the Gulf. This region was divided between people of two language groups: in the south, Sumerian-speakers, in the north, Semitic speakers, or Akkadians.
Each Sumerian city was the center of a small city-state, consisting of the city itself and its surrounding territory – farmlands, gardens and orchards in the irrigated land near the city, grazing land for herds of cattle and flocks of sheep and goats on the arid land further out, between the cities.
The city was surrounded by a wall. A large Sumerian city held between 30,000 and 40,000 inhabitants, and one of the largest, Lagash, had a territory of 2,880 square kilometers. At the heart of the city, both physically and metaphorically, stood the temple to its patron god.
The Sumerians regarded their city-god as the true owner of the city. This may originally have had its earthly expression in the temple owning all the land in the city-state, but by the Early Dynastic period this was no longer the case. The temple owned an estimated third of the arable land in each city-state, and was therefore a major economic unit. It used the revenue to maintain the priest, officials, craftsmen and other servants of the temple; to store as a provision against drought; and to exchange with goods from abroad – international trade was in the hands of the temple or palace.
By the mid-third millennium BCE secular rulers had usurped much of the political and economic power of the temple. The ruler of a city-state came to be viewed as chosen by the god of the city to be responsible for the safety and prosperity of the people. The earliest rulers were probably both the high priest and ruler, and Mesopotamian kings continued to have priestly functions throughout their history.
From an early date, however, there was a trend for temple and palace to become separate institutions. Even if the rulers started out as the high priests, it is easy to see how this development took place. It is easier for a community to identify with a personal leader rather than an institution, and the high priest of a town would have been invested with charismatic authority. The office would in all probability have been hereditary within a particular family, who would have taken on the attributes of a royal dynasty.
With increasing warfare between states the leader’s position would have become ever more crucial, and so more prestigious, and the ruler’s office would have outgrown the temple context in which it had its roots. In due course the Palace would have developed as a distinct institution within the state, and by the Early Dynastic period the royal palace was probably as wealthy and powerful as the temple.
What we know of Sumerian history in the Early Dynastic period is one of warfare, between city-states and with foreign invaders. The cities strove to subdue one another, and one city-state after another – Kish, Uruk, Ur, Nipur, Lagash, Umma – achieved a position of dominance over some or all of the other cities of southern Mesopotamia, and beyond.
In this rather tedious power-struggle, certain issues seem to have been at stake. It is clear that some wars were a straightforward conflict over resources – land, water, trade routes. Over and above these, however, there seemed to be two goals that an ambitious king would aim for.
Firstly, domination of Nippur gave him control over the religious center of Sumer, because it was in this city that the temple of the chief Sumerian god, Enlil, was located. This seems to have been a center of pilgrimage, and possessing it gave a ruler enormous prestige. His patronage of the temple legitimized his status as overlord of other city-states.
Secondly, controlling Kish seems to have been key to controlling the Semitic lands of Akkad, just north of the Sumerian heartlands, which in turn gave a ruler a huge strategic advantage viz-a-viz the other rulers. These two cities therefore figure prominently in the power-struggles of the period.
Suddenly in the late 3rd millennium BCE there burst onto the scene the first of history’s great conquerors, Sargon of Akkad. His empire wrought great changes within Mesopotamia, and his career cast a long shadow over later history as ambitious kings strived to emulate his achievements.
Sargon of Akkad
To the north-west of the Sumerian heartland lay the region later known as Akkad, inhabited by a Semitic people. In later history the Semites became associated with a nomadic style of life – one need think only of the Arabs to see why – but there is no evidence for this at this early period. The Semitic peoples of Akkad were by and large not nomads, and during the Early Dynastic period fully shared in the Sumerian civilization to their south. They lived in similar city-states, worshipped the same gods and goddesses, followed the same artistic and architectural styles, and used the same cuneiform script. The only difference was that they spoke a different language, later known as Akkadian.
Bronze Head of a King most likely Sargon of Akkad
In the center of this Semitic area stood the Sumerian city of Kish, and in c. 2334 BCE an official of humble origin, Sargon, seized control of the city and became its ruler. Being a Semite himself, he based his power on the local Semitic population, with whose help he defeated the Sumerians and became overlord of both Sumer and Akkad. Sargon then consolidated his power in a way no other king before him seems to have done. He founded a new capital, Agade (from which the term “Akkad” comes – but we do not yet know the exact location of the city); he placed his own officials as governors of the defeated Sumerian city-states; he confiscated large tracts of land in the old city-states, probably from both the palaces and temples, and turned them into royal domains under his own officials to support his personal wealth and power; and he made Akkadian the language for official business.
Having thus secured his power in southern Mesopotamia, he expanded it on a scale never before attempted. He subjected Elam in the east, Mari in northern Mesopotamia, Ebla and other cities in Syria, and carried his power as far as the Mediterranean Sea and the Taurus mountains. He probably even led an expedition into Asia Minor.
On his death in 2279 BCE there were widespread revolts, which his son, Rimush, dealt with vigorously. Even so, it appears that areas of northern Mesopotamia and Syria temporarily fell away from Akkadian rule, and it was not until Sargon’s grandson, Naram-Sin (2254-2218 BCE) came to the throne that Akkadian power revived.
Naram-Sin reclaimed all the lost territory and expanded the Akkadian empire still further. He spent almost his entire reign on campaign, re-imposing his family’s rule in northern Mesopotamia and Syria (sacking Mari and Ebla in the process), and extending Akkadian power into eastern Turkey. He departed from Mesopotamian tradition when he became the first Mesopotamian ruler to claim the status of a god within his own lifetime.
Naram-Sin was the last great king in Sargon’s line. With his death revolts and invasions occurred throughout the empire. Elam was lost, and several Sumerian cities revolted. Northern Mesopotamia, Syria and the Anatolian regions fell away from the empire. Finally the Guti, a barbarian hill people from the Zagros mountains, invaded Mesopotamia, put an end to Akkadian power once and for all, and installed themselves as the new rulers of Sumer and Akkad.
Thus ended the first real empire in world history. Sargon and his successors made an immense impression of the ancient Middle Eastern imagination. The memory of Sargon himself became surrounded by legend, and an example to ambitious rulers in the region for centuries after his death.
The geographical horizons of the people of southern Mesopotamia were vastly enlarged, and the influence of their civilization greatly enhanced in the surrounding regions. Northern Mesopotamia was brought fully within the fold of Sumerian/Akkadian civilization, as were other peoples further afield such as the Hurrians, Lullubi and Elamites. In southern Mesopotamia, Semites and Sumerians had become so intermingled that the region should hereafter be called “Sumer and Akkad”. Akkadian was established as the language of government alongside Sumerian.
The period of Akkadian rule had worked other changes in Sumerian civilization. For more than a century the main city-states of Sumer had been ruled by Akkadian governors. The old Sumerian rulers had not been displaced, however; they just answered to a higher (earthly) power. To support the Sargonid regime, large portions of the old temple and palace estates had been confiscated and handed over to the newcomers. With the passing of Akkadian rule the new rulers of the cities took over the land and brought it under their direct ownership, thus greatly expanding the wealth and power of the Palace at the expense of the Temple. The rulers now dominated their city-states in a new and more complete way.
On the other hand, one of the more lasting changes brought about by Sargon and his successors was that after their time Sumer and Akkad became more of an integrated political unit. The rulers of individual city-states were henceforth no longer as independent as they had once been, and were now usually vassals of an overlord, who called himself the king of Sumer and Akkad.
The Guti Interlude
The first of these overlords were the Guti kings. In the closing chapter of the Akkadian story the Guti invaded southern Mesopotamia, ravaged the country, sacked the capital and then occupied Sumer and Akkad as the ruling group. However, they were few in number and apparently only able to occupy a few strategic locations such as Nippur and probably Ur. Most of the city-states were left to their own devices so long (presumably) as they continued to send tribute to the Gutian kings, and some, notably Lagash, thrived economically and culturally.
After almost a hundred years of dominance, the Guti were driven out in 2120 BCE. Within a few years, the ruler of Ur, called Ur-Nammu, had establishing himself as king of Sumer and Akkad.
A brick stamped with the name of Ur-Nammu of U
Reproduced under Creative Commons 4.0
Ur-Nammu (2112-2095 BCE) founded the 3rd dynasty of Ur, under whom southern Mesopotamia knew almost a century of peace and prosperity. He promoted agricultural expansion by enlarging the system of canals, and he carried out a spectacular building program in the cities of his kingdom.
Most famously, Ur-Nammu built a series of ziqqurats, pyramid-like structures which soared over the cities that housed them (indeed, some scholars believe they were inspired by the great Pyramids of Egypt, though they were not royal tombs but the final stage in a long history of Sumerian temple architecture going back thousands of years). The greatest of these was at Ur itself, at 40 meters or more in height the most magnificent example of Sumerian architecture remaining today.
A Centralized State
Ur-Nammu died in battle and was succeeded by his son, Shulgi, who in his long reign (2094-2047 BCE) carried out a thoroughgoing reform of his kingdom, breathtaking in its scope. A law code was drawn up for the entire kingdom, weights and measures standardized, and a uniform tax system imposed across the land. The tribute raised (grain, sheep, cattle and so on) was sent to a central storehouse near Nippur to be distributed to where the government ordered it: to feed the labor digging and maintaining canals and roads, building temples; or to support the lavish court at the capital.
Manufacturing centers were set up throughout the kingdom to produce a wide range of goods – leathers, textiles, flour, beer, pottery, cooking utensils and so on. International commerce was in the hands of state officials, in line with a long Sumerian tradition, but conducted on a much larger scale than hitherto.
To administer this highly centralized system an enlarged bureaucracy was built up, and the cuneiform script improved to help officials cope with the increased work load. The previous rulers of the different city-states of Sumer and Akkad were kept in their positions, but were now treated as subordinate officials within a national structure, their loyalty and efficiency inspected by royal officials.
The kings of Ur expanded their territories by conquest, and built up a network of allied states. The lands of northern Mesopotamia were turned into provinces, and beyond these lands, Elam, Mari and other states were drawn into a network of marriage alliances with the royal family of Ur. A network of roads knitted this geo-political structure together. Standing head and shoulders above all other kings, Shulgi, following in the steps of Naram-Sin, proclaimed himself a god in his own lifetime.
Decline and Fall
The empire of Ur lasted for around twenty years after Shulgi’s death before unravelling. One by one the eastern provinces seceded from the empire, and in the west Semitic nomads new to history, the Amorites, exerted pressure and then broke through the defenses, penetrating into the heart of the kingdom. Then the heartland of Akkad and Sumer itself began to break away, with the rulers of the city-states proclaiming their independence. Finally, in 2004 BCE, the Elamites invaded, took Ur, sacked the city and led the last king of Ur away captive.
The centuries after the empires of Akkad and Ur were ones of division and invasion. In due course another great conqueror emerged, who briefly held the Mesopotamian world together. But by now new centers of power and civilization were emerging, and the days of southern Mesopotamian dominance were nearing an end.
After the fall of Ur, southern Mesopotamia remained fragmented amongst a multitude of kingdoms for more than two centuries. There was constant war as the kings struggled to dominate each other, aiming to become the next overlord of Sumer and Akkad. The most important states were Isin and Larsa, with Isin predominating for the first century or so, and Larsa in the next.
The kings of both these states, although of foreign origin (Isin’s royal family came originally from Mari, Larsa’s were of, first Amorite, then Elamite stock), saw themselves as the natural heirs of the old Sumerian rulers. They patronized Sumerian art and literature, embellished the great city of Ur with many new temples, and had their official inscriptions written in the Sumerian language – even though by now Akkadian was the everyday language of government and administration.
While Isin, Larsa and other kingdoms were thus competing with one another, the region was being settled by clans from the desert. These were the Amorites, who arrived as barbarian semi-nomads but soon adopted the civilization of Sumer and Akkad.
The Amorites founded many small kingdoms, and had a lasting impact upon the social and economic life of the region. The independence of the old city states, and the political and administrative structures that they embodied, were finally ended. The new kings took large pieces of the land for themselves, and, keeping some to be worked by tied peasants for the maintenance of the Palace, distributed the rest of it amongst their families, friends and followers. A new landowning class thus arose.
Temples lost their economic privileges and became landowners like many others; and like all, subject to royal taxes. The large temple and palace workshops, let alone the enormous factories of the kings of Ur, were a thing of the past, with small private workshops now proliferating. Even international trade, hitherto a jealously guarded monopoly of temple or palace, was now more in private hands.
Finally, the religious sphere was not untouched. The new Amorite kings were more taken up with local concerns, and the local gods became more important to them. The old national shrine of Nippur declined in importance, and with it the great god Enlil. This in due course created a vacuum for a new chief god to fill.
One of the Amorite chiefs settling in the region founded a small kingdom based on the hitherto unimportant town of Babylon (1894 BCE). Over the next sixty years or so he and his successors gradually expanded their power, so that by the end of this period they ruled almost all the land of Akkad. Hammurabi ascended the throne of Babylon in 1792, and over the course of a long reign (1792-49 BCE) turned his territory into a large empire covering the whole of Mesopotamia and beyond.
This bust, known as the “Head of Hammurabi”, is now thought to predate
Hammurabi by a few hundred years.
Reproduced under Creative Commons 3.0
Throughout his disparate domains Hammurabi pursued a centralizing policy. Local government remained in the hands of local leaders, but above this a hierarchy of royal officials governed the empire, with the king taking a direct and active interest in the detailed affairs of his kingdom.
In many ways Hammurabi acted in the time-honored fashion of a conscientious Sumerian ruler: rebuilding and repairing the ancient temples, digging new canals and maintaining old ones, seeing justice done – with a view to which he issued his famous Law Code towards the end of his reign, following the example of previous Mesopotamian rulers.
In other ways he was a genuine innovator. For the first time a new socio-political institution appears in Mesopotamia, the fief, given to soldiers and others in return for military and other service. This was perhaps an attempt to create a class of followers distributed throughout the empire whose loyalty could be counted on to bolster the power of Hammurabi and his dynasty.
Hammurabi’s death was followed by mass revolts. Hammurabi’s son, Samsu-iluna (1749-1712 BCE), fought valiantly to keep his father’s political creation together, but without success. Southern Mesopotamia, ancient Sumer, fell under the control of the Sea-land dynasty – not before the historic centers of Ur and Uruk had been put to the torch – and northern Mesopotamia fell under the control of Assyria.
Hammurabi’s successors were henceforth confined to the old region of Akkad. They preserved the Babylonian kingdom for another century. However, in 1595 BCE a large raid conducted by the king of the Hittites sacked Babylon, and the king of Babylon was deposed, and probably killed. The Hittites withdrew almost immediately, as their king had pressing matters at home to deal with, and into the political vacuum they left behind stepped the ruler of the Kassites, Agur II, taking the throne of Babylon and founding a dynasty which would last 438 years – the longest in Mesopotamia’s history.
The Kassites were a people who had lived in the central Zagros region for millennia, although since around 2000 BCE they had come under the rule of an Indo-European speaking ruling class, giving them a warlike streak which they do not appear to have had before.
Although foreigners in Babylon, they provided their new kingdom with much needed peace, stability and economic revival. Apart from a war in which they conquered the Sea-Land kingdom and so reunited southern Mesopotamia – which from this date is known to scholars as Babylonia – they indulged neither in foreign adventures not domestic strife for many long years. With Assyria they signed a treaty dividing Mesopotamia between the two powers. At home they ruled within the hallowed traditions of Mesopotamian monarchs – worshipping the ancient gods, digging canals and above all rebuilding the old temples.
Fortunately for generations of scholars thousands of years in the future, they also patronized Mesopotamian literature by overseeing the collecting, organizing, editing and storage of thousands of cuneiform tablets in the royal libraries.
The Kassites continued to rule Mesopotamia for several centuries. In 1235 BCE, however, a dual invasion of Babylonia by Assyria and Elam led to the Assyrians installing their own governors as rulers of Babylon. Assyria immediately entered a period of political instability, with a series of palace coups, and the Kassite-Babylonians soon revolted (1227) and restored their independence. Elam remained a threat, however, and in 1160 BCE invaded Babylonia again. They did so with a huge army, and plundered southern Mesopotamia mercilessly. Many Mesopotamian masterpieces, including the great statue of Marduk, were taken away to Susa, the capital of Elam. The last Kassite king was ousted from his throne in 1157 BCE, and Babylon occupied by Elam.
The Elamites soon evacuated Babylonia, probably because they were coming under pressure on their northern and eastern flanks from new groups of peoples moving into Iran. Babylon again had a native dynasty on her throne, and the most famous of these kings was Nebuchadnezzar I (c. 1124-1103 BCE), who gained lasting fame for a highly successful campaign into Elam which resulted in the return of the statue of Marduk to Babylon.
By this date, the ancient countries of Mesopotamia were all under threat from large-scale migrations of Aramaean tribes; and indeed the whole history of the region now takes on a new character, as the Middle East enters a phase of barbarian invasion and the eclipse of the ancient centers of civilization. This period lasts for several centuries, and is followed by one which sees the rise of a series of enormous empires in the region. The future of Mesopotamia is as one region amongst many others.
The main sources I have used for the history of ancient Mesopotamia are:
Roux, G., Ancient Iraq, Penguin, 1992, is a very readable overview of the subject for the general reader.
Saggs, H.W.F. The Babylonians, Macmillan, 1988, is, despite its name, a comprehensive and scholarly coverage of ancient Mesopotamian civilization up to the end of the Neo-Babylonian empire in the 6th century BC.
Roaf, M., A cultural atlas of Mesopotamia and the Ancient Near East, Andromeda, 1990, is a superbly illustrated and highly informative introduction to the subject.
A lavishly illustrated work on archaeology for the general reader which includes good coverage of ancient Mesopotamia, is Renfrew, C. (ed.), Past Worlds: The Times Atlas of Archaeology, Times Books, 1995, p. 98-9; 122-7; 132-5; 154-7.
A work on general archaeology aimed more at students, but readable and with very good coverage of ancient Mesopotamia, is Scarre, C. (ed.), The Human Past, Thames & Hudson, 2005, p. 232, 432ff.
For an insightful look at government in ancient Mesopotamia, see Finer, S. E., The History of Government, I, Ancient Monarchies and Empires, OUP, 1999, p. 104ff.
The University of Chicago has produced a superb site on Ancient Mesopotamia.
An informative website on ancient Mesopotamia is the British Museum’s Ancient Mesopotamia.
Wikipedia has its usual vast amount of information on Ancient Mesopotamia.