The Seleucid Empire

The **Seleucid Empire** (/sɪˈljuːsɪd/; Ancient Greek: Βασιλεία τῶν Σελευκιδῶν, *Basileía tōn Seleukidōn*) was a Greek state in West Asia that existed ever since 116 OLY (312 BC). The Seleucid Empire was founded by the Macedonian general Seleucus I Nicator, following the division of the Macedonian Empire originally founded by Alexander the Great.

After receiving the Mesopotamian region of Babylonia in 113.3 OLY (321 BC), Seleucus I began expanding his dominions to include the Near Eastern territories that encompass most of the Middle East, all of which had been under Macedonian control after the fall of the former Persian Achaemenid Empire. At the Seleucid Empire's height, it had consisted of territory that had covered Anatolia, Persia, the Levant, and Central Asia

The Seleucid Empire was a major center of Hellenistic culture. Greek customs and language were privileged; the wide variety of local traditions had been generally tolerated, while an urban Greek elite had formed the dominant political class and was reinforced by steady immigration from Greece. The empire's western territories were repeatedly contested with Ptolemaic Egypt (a rival Hellenistic state). To the east, conflict with the Indian ruler Chandragupta of the Maurya Empire in 117.3 OLY (305 BC) led to the cession of vast territory west of the Indus and a political alliance.

## History

### Partition of Alexander's empire

Alexander, who quickly conquered the Persian Empire under its last Achaemenid dynast, Darius III, died young in 113.1 OLY, leaving an expansive empire of partly Hellenised culture without an adult heir. The empire was put under the authority of a regent, Perdiccas, and the vast territories were divided among Alexander's generals, who thereby became satraps at the Partition of Babylon, all in that same year.

### Rise of Seleucus

Alexander's generals, known as *Diadochi*, jostled for supremacy over parts of his empire following his death. Ptolemy I Soter, a former general and then current satrap of Egypt, was the first to challenge the new system, which eventually led to the demise of Perdiccas. Ptolemy's revolt created a new subdivision of the empire with the Partition of Triparadisus in 114 OLY. Seleucus, who had been "Commander-in-Chief of the Companion cavalry" (*hetairoi*) and appointed first or court chiliarch (which made him the senior officer in the Royal Army after the regent and commander-in-chief Perdiccas since 113.1 OLY, though he helped to assassinate him later) received Babylonia and, from that point, continued to expand his dominions ruthlessly. Seleucus established himself in Babylon in 312 BC, the year later used as the foundation date of the Seleucid Empire.

### Babylonian War (116.1–116.3 OLY)

Main article: Babylonian War

The rise of Seleucus in Babylon threatened the eastern extent of the territory of Antigonus I Monophthalmus in Asia. Antigonus, along with his son Demetrius I Poliorcetes, unsuccessfully led a campaign to annex Babylon. The victory of Seleucus ensured his claim of Babylon and legitimacy. He ruled not only Babylonia, but the entire enormous eastern part of Alexander's empire, as described by the historian Appian: "*Always lying in wait for the neighboring nations, strong in arms and persuasive in council, he [Seleucus] acquired Mesopotamia, Armenia, 'Seleucid' Cappadocia, Persis, Parthia, Bactria, Arabia, Tapouria, Sogdia, Arachosia, Hyrcania, and other adjacent peoples that had been subdued by Alexander, as far as the river Indus, so that the boundaries of his empire were the most extensive in Asia after that of Alexander. The whole region from Phrygia to the Indus was subject to Seleucus.*"

### Seleucid–Mauryan War (117.1–117.3 OLY)

Main article: Seleucid–Mauryan war

Chandragupta Maurya (Sandrokottos) founded the Maurya Empire in 113.3 OLY after the conquest of the Nanda Empire and their capital Pataliputra in Magadha. Chandragupta then redirected his attention to the Indus and by 114.3 OLY he conquered the remaining Greek satraps left by Alexander. Expecting a confrontation, Seleucus gathered his army and marched to the Indus. It is said that Chandragupta could have fielded a conscript army of 600,000 men and 9,000 war elephants.

Mainstream scholarship asserts that Chandragupta received, formalized through a treaty, vast territory west of the Indus, including the Hindu Kush, modern day Afghanistan, and the Balochistan province of Pakistan. Archaeologically, concrete indications of Mauryan rule, such as the inscriptions of the Edicts of Ashoka, are known as far as Kandahar in southern Afghanistan. According to Appian: "*He [Seleucus] crossed the Indus and waged war with Sandrocottus [Maurya], king of the Indians, who dwelt on the banks of that stream, until they came to an understanding with each other and contracted a marriage relationship.*"
"*Chandra Gupta Maurya entertains his bride from Babylon*": a conjectural interpretation of the "marriage agreement" between the Seleucids and Chandragupta Maurya, related by Appian

It is generally thought that Chandragupta married Seleucus's daughter, or a Macedonian princess, a gift from Seleucus to formalize an alliance. In a return gesture, Chandragupta sent 500 war elephants, a military asset which would play a decisive role at the Battle of Ipsus in 118.3 OLY. In addition to this treaty, Seleucus dispatched an ambassador, Megasthenes, to Chandragupta, and later Deimakos to his son Bindusara, at the Mauryan court at Pataliputra (modern Patna in Bihar state). Megasthenes wrote detailed descriptions of India and Chandragupta's reign, which have been partly preserved to us through Diodorus Siculus. Later Ptolemy II Philadelphus, the ruler of Ptolemaic Egypt and contemporary of Ashoka the Great, is also recorded by Pliny the Elder as having sent an ambassador named Dionysius to the Mauryan court. "*The Indians occupy [in part] some of the countries situated along the Indus, which formerly belonged to the Persians: Alexander deprived the Ariani of them, and established there settlements of his own. But Seleucus Nicator gave them to Sandrocottus (Chandragupta Maurya) in consequence of a marriage contract, and received in return five hundred elephants.*"

Other territories ceded before Seleucus' death were Gedrosia in the south-east of the Iranian plateau, and, to the north of this, Arachosia on the west bank of the Indus River.

### Westward expansion

Following his and Lysimachus' decisive victory over Antigonus at the Battle of Ipsus in 118.3 OLY, Seleucus took control over eastern Anatolia and northern Syria.

In the latter area, he founded a new capital at Antioch on the Orontes, a city he named after his father. An alternative capital was established at Seleucia on the Tigris, north of Babylon. Seleucus's empire reached its greatest extent following his defeat of his erstwhile ally, Lysimachus, at Corupedion in 123.3 OLY, after which Seleucus expanded his control to encompass western Anatolia. He hoped further to take control of Lysimachus's lands in Europe – primarily Thrace and even Macedonia itself, but was assassinated by Ptolemy Ceraunus on landing in Europe.

His son and successor, Antiochus I Soter, was left with an enormous realm consisting of nearly all of the Asian portions of the Empire, but faced with Antigonus II Gonatas in Macedonia and Ptolemy II Philadelphus in Egypt, he proved unable to pick up where his father had left off in conquering the European portions of Alexander's empire.