History Seleucid Empire

The Seleucid Empire was a Hellenistic state ruled by the Seleucid dynasty, which existed from 312 BC to 63 BC; it was founded by Seleucus I Nicator following the division of the Macedonian empire vastly expanded by Alexander the Great. Seleucus received Babylonia and, from there, expanded his dominions to include much of Alexander's near eastern territories. At the height of its power, it included central Anatolia, Persia, the Levant, Mesopotamia, and what is now Kuwait, Afghanistan, and parts of Pakistan and Turkmenistan.

The Seleucid Empire was a major center of Hellenistic culture that maintained the preeminence of Greek customs where a Greek political elite dominated, mostly in the urban areas. The Greek population of the cities who formed the dominant elite were reinforced by immigration from Greece. Seleucid expansion into Anatolia and Greece was abruptly halted after decisive defeats at the hands of the Roman army. Their attempts to defeat their old enemy Ptolemaic Egypt were frustrated by Roman demands. Having come into conflict with Chandragupta Maurya of the Maurya Empire, after several defeats, Seleucus entered into an agreement with Maurya where he ceded vast territory west of the Indus, including the Hindu Kush, modern day Afghanistan, and the Balochistan province of Pakistan and offered his daughter for marriage to the Emperor to formalize the alliance. Much of the eastern part of the empire was conquered by the Parthians under Mithridates I of Parthia in the mid-2nd century BC, yet the Seleucid kings continued to rule a rump state from Syria until the invasion by Armenian king Tigranes the Great and their ultimate overthrow by the Roman general Pompey.

Alexander, who quickly conquered the Persian Empire under its last Achaemenid dynast, Darius III, died young in 323 BC, leaving an expansive empire of partly Hellenised culture without an adult heir. The empire was put under the authority of a regent in the person of Perdiccas, and the 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 (the Diadochi) jostled for supremacy over parts of his empire. Ptolemy, a former general and the satrap of Egypt, was the first to challenge the new system; this led to the demise of Perdiccas. Ptolemy's revolt led to a new subdivision of the empire with the Partition of Triparadisus in 320 BC. 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 323 BC, 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 used as the foundation date of the Seleucid Empire. He ruled not only Babylonia, but the entire enormous eastern part of Alexander's empire, as described by 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.

Seleucus went as far as India, where, after two years of war, he reached an agreement with Chandragupta Maurya, in which he gave his daughter in marriage to Chandragupta and exchanged his eastern territories for a considerable force of 500 war elephants, which would play a decisive role at Ipsus (301 BC). Strabo, in his Geographica, wrote: