What was the impact of the Babylonian War (311-309 BCE) on the Hellenistic World?


One of the most important conflicts in the Hellenistic world was the so-called Babylonian War. This was a brief but decisive war that was fought in modern Iraq and had far-ranging consequences for the Hellenistic World. The Babylonian War was fought between 311–309 BC between the Diadochi (successors) kings Antigonus I Monophthalmus and Seleucus I Nicator. The conflict was considered to have led to the foundation of the Seleucid Empire and to have ensured that the Empire of Alexander the Great would never be reunited. The outcome of the war was to ensure that the dream of a World-Empire as envisioned by Alexander the Great would never become a reality.

A coin of Seleucus I Nicator


Alexander the Great had invaded the Persian Empire in 333 BCE with a large army of Macedonian and Greek warriors. In a series of great battles including Issus, Gaugamela and Granicus River he smashed the mighty Persian army and conquered the entire Persian Empire. Alexander later campaigned in Central Asia and in North-West India. As he went he found cities and colonies of Greeks and Macedonians and soon he had established an Empire that stretched from the Danube to the Punjab in India. After returning from his campaign in India, Alexander fell ill, probably from a fever and he died. His son was too young to succeed him, and his brother was deemed to be unsuitable. Alexander had made many plans for further conquests, but he had failed to appoint an heir. Soon his empire began to fall apart. The power vacuum after the untimely death of Alexander was soon filled by his generals[1]. The army of the great King was divided up by his former generals and they took over many territories and ruled as independent sovereigns. The various generals began to fight among themselves in a series of civil wars to reunite the Empire of Alexander or to carve out a kingdom for themselves. The first War of the Diadochi saw Perdiccas, attempt to marry Alexander’s sister and to reunite the Empire under him, but he was defeated by a coalition of generals led by Ptolemy. After the defeat of Peridiccas the Empire was portioned between the generals and they all recognized Alexander’s young son as the king of his father’s Empire, but the ‘real rulers were the generals’[2]. Soon they generals who were really only warlords began to style themselves as monarchs, often blending local ideas about monarchy with Macedonian ideas [3]. The peace agreement did not last and there were to be two further civil wars, the Second and the Third Diadochi. During the second Diadochi War, the mother, wife and the son of Alexander were murdered in Greece and the dynasty of Alexander came to an end. In the Second Diadochi war, one of Alexander’s old general Antiochus I Monophthalmus (One-eyed) became the most powerful of all the successors. He came to dominate much of the modern Middle East, Turkey and most of Greece. The other generals were fearful of the growing power of Antiochus[4]. The Third Diadochi War was a war between Antigonous I and Ptolemy, Lysimachus, and Cassander. They were joined by Seleucus who had seized some of the Far Eastern Satrapies of Alexander’s Empire. Seleucus had earlier been expelled by Antigonous from Babylon and had been forced to retreat to his Central Asian territories. He later returned, after receiving some support from Ptolemy. This was to lead to the Babylonian War, which is regarded as being part of the Third Diadochi War.

Babylonian War

Seleucus, reinforced with veterans of Alexander’s campaigns reached Babylon in 311. He was soon recognized as the new ruler. Antigonus had made himself unpopular in the city and its hinterland. Only the citadel defied him and was held by a garrison that was loyal to Antigonus. Seleucus was forced to besiege the fortress and in the end, he captured it by flooding it. The Macedonian monarch then sent two of his satraps to destroy Seleucus but he was an able general and even though he had inferior forces he ambushed the satraps and destroy them and their armies. Seleucus was a shrewd man and he could persuade the Iranians who served with the satraps of Antiochus, to join his forces. By now Seleucus was a serious challenge to Antigonus, he had largely been able to contain the attacks of Ptolemy from Egypt and was even expanding his territories at the expense of Cassander and Lysimachus. Seleucus could expand his territory and he seized southern Iraq and the greater part of Iran. Antigonus could secure his position and even forced his enemies to sign the Peace of Dynasts, which was greatly, to his advantage[5]. Only Seleucus was defying Antiochus and the one-eyes monarch ordered his son to attack and seize Babylon. However, Seleucus could inspire not only the Macedonians and the Greeks in his army but also the local population[6]. He was able to put up such resistance that he forced Demetrius to abandon his siege of Babylon. Antigonus was enraged and assembled a huge army in 310 BC and advanced on Babylon. In the autumn of 310 BCE, Antigonus was able to fight his way into Babylon, but he was forced back after stiff resistance. The aging monarch was forced to retire to the north but he returned the following year. He met the army of Seleucus outside Babylon[7]. The night before the day the two armies were to clash, Seleucus ordered his men to eat their rations. The next morning while the Antigonous army was having its breakfast, Seleucus soldiers attacked Antigonus' soldiers and they achieve a total victory. After this Seleucus was the ruler of a vast territory that reached from Iraq to Afghanistan.

A Macedonian soldiers attacking a Persian

Babylonian War and the alliance with Ptolemy

Seleucus needed the assistance of Ptolemy who was the de-facto monarch in Egypt. The support that the Macedonian ruler of Egypt, especially the veterans he supplied were crucial in the defeat of Antigonus and his son Demetrius. Ptolemy wanted Seleucus to distract Antigonus army in the east so that the Antagonids would not invade his Egyptian territories. The Babylonian War also allowed Ptolemy to survive an onslaught on his kingdom. The support that Ptolemy afforded Seleucus cemented the alliance between the two Macedonians. Earlier Seleucus had served under Ptolemy as his admiral and the men had a close relationship. This relationship was to prove crucial in the years ahead. Their understanding was based on the acceptance that both had legitimate spheres of influence, Seleucus in the East and Ptolemy in Egypt, this was crucial as it effectively meant that there would be no further attempts to reunite the Empire of Alexander the Great. The two rulers’ understandings were also to be very important in the fourth Diadochi war.

Victory in the Fourth Diadochi War

Antigonus was not deterred by his defeat outside the walls of Babylon. In 301 BCE he ordered his son Demetrius to seize those parts of Greece, which were part of the Kingdom of Cassander. The other Diadochi kings including Seleucus formed a coalition to defend their interests and to ensure that the Antigonid’s did not become too powerful. The armies of Ptolemy and Seleucus marched into modern Turkey and they confronted a huge army under the leadership of Antigonous[8]. The two armies clashed near the village of Ipsus, today in southern Turkey. The battle was a decisive victory for Seleucus and his allies. Antigonus was killed during this battle and his son escaped to Greece with a small force. The alliance partitioned the territory of Antigonous and Seleucus secured Syria and Lebanon and his Empire stretched from the Mediterranean to the Hindu Kush. The army of Seleucus was critical to the defeat of Antigonus, the war elephants he had received from Indian proved decisive[9]. However, the foundation for the victory of Ipsus had been established during the Babylonian War. Because Antigonus was unable to dislodge Seleucus from Babylon, the latter could create a huge empire in the east. This made him the most powerful of all the Hellenistic kings and that he could raise a huge army that made the defeat of Antigonus almost inevitable. The victory of the founder of the Seleucid dynasty in Babylon meant that Antigonus was doomed and that there would be no further attempt to resurrect the Empire of Alexander. Soon after Ipsus, there emerged three successor kingdoms, the Seleucid Empire, the Ptolemaic Empire, based in Egypt and the Kingdom of Macedonia. This led to a long period of stability and peace which was a crucial factor in the brilliant flowering of Hellenistic culture.

A bust of Seleucus

Birth of the Seleucid Empire

Before the Babylonian War, Seleucus was just another warlord. In the aftermath of the Babylonian War, he could greatly expand his empire. The victor turned east to consolidate his vast territories and after an unsuccessful campaign in modern Pakistan, he concluded a treaty with Chandragupta Mauryan. The Indian emperor received the extreme eastern parts of the of the Empire of Alexander and in return, gave Seleucus a formidable force of several hundred war elephants. Despite these concession by the Macedonian, he was the strongest of the Diadochi and this was to prove decisive in the years ahead. There are many reasons why Seleucus entered into an agreement with the Mauryan Empire. He recognized that he could not defend the territories he conceded, and their concession allowed him to concentrate on his core territories. The Macedonian on his return could use the wealth of Babylon to create a huge army. He also made Babylon and its hinterland in Southern Iraq the core area of his newly emerging Empire[10]. With the resources available to him he could set up an administration and developed an efficient system of governance for his new territories. Seleucus founded the city of Seleucia, named after himself and this became his new capital[11]. By 305 BC Seleucus was the de-facto ruler of the greatest of the successor kingdom and he built a state that was to last. A brilliant administrator he created a state that was based on a system of semi-autonomous satrapies and Greek and Macedonian colonies. The state he built was enduring and it even survived his assassination in 281 BCE.


The victory of Seleucus in the Babylonian War was a turning point in the struggles of the successor of Alexander the Great. Because Antigonus was unable to recapture Babylon, it allowed Seleucus to create a vast Empire in the east. The resources that he could raise, including war elephants, proved decisive in the Fourth Diadochi War. The importance of Seleucus victory in the war of 311-309 BCE was that it virtually guaranteed the destruction of the Antigonid kingdom and ended the last attempt to unify the Macedonian successor kingdoms. After the death of Cassander and Lysimachus in rapid succession, the Ptolemies and the Seleucids controlled the majority of Alexander's former empire, with Macedonia being ruled by a member of the Antigonid dynasty until the 1st century. The other important consequence of the Babylonian War was that a new dynasty emerged; the Seleucid dynasty. Seleucus was so successful that he could hand his sprawling Empire over to this son and heir who was a competent leader and ruler. The Macedonian was able to establish a dynasty because of his victory over Antigonus. The dynasty that he found was to rule large areas of Asia for almost two hundred years and played a decisive role in the history of that region. The last Seleucid king was only deposed by Pompey the Great in the first century BC. This would not have been possible without his victory in the Babylonian War.


  1. Green, Peter Alexander the Great and the Hellenistic Age (London, Phoenix, 2008), p. 256
  2. Bennett, Bob; Roberts. The Wars of Alexander's Successors 323–281 BC; Volume I: Commanders & Campaigns. Pen and Sword Books, 2008), p. 115
  3. Bennett, Bob; Roberts, Mike (2009). The Wars of Alexander's Successors 323–281 BC; Volume II: Battles and Tactics. Pen and Sword Book, 2009), p. 113
  4. Bennet, vol ii,p. 45
  5. Plutarch, Life of Demetrius the Besieger, vii
  6. Plutarch, vii
  7. Bennet vol ii, p 145
  8. Davis, Paul K.. 100 Decisive Battles from Ancient Times to the Present: The World’s Major Battles and How They Shaped History (Oxford, Oxford University Press, 1990), p. 134
  9. Davis, p. 167
  10. Bennet, vol ii, p. 67
  11. Paul J. Kosmin, The Land of the Elephant Kings: Space, Territory, and Ideology in the Seleucid Empire (Cambridge, MA: Harvard University Press, 2014), p. 114