Seleucid dynasty
Seleucid Kingdom, an ancient realm that centered mainly in Syria. It was founded by Seleucus, one of the Diadochi (Successors), the group of generals in the army of Alexander the Great to whom control of Alexander's empire fell after his death in 323 B.C . Within a year the Diadochi were fighting each other for supreme control. In 312 B.C . Seleucus seized control of Babylonia. As Seleucus I, later called the Conqueror, he created an empire by annexing Syria, Asia Minor, and areas eastward to India. He founded as his capitals Seleucia-on-the-Tigris, near Babylon, and Antioch, in northern Syria. Both cities became major trade centers.
The civilization of the Seleucid Kingdom was Hellenistic, or Greek, influenced by native Asian traditions. The kings, for example, spoke Greek, but they ruled in the Oriental manner—as absolute monarchs.
Seleucus I was murdered by a rival in Macedonia in 280 B.C. His descendants included five other kings named Seleucus and 12 kings named Antiochus. The most notable among them were Antiochus III (reigned 223–187 B.C .) and Antiochus IV (reigned 175–163 B.C .). The empire gradually disintegrated under the later kings. The chief rivals were the Ptolemies of Egypt, with whom a succession of wars was fought. The Parthians, a native group in Persia, declared their independence from Seleucid rule and began to found their own empire in about 248 B.C . By 129 B.C . the Seleucid Kingdom had been reduced to a small area in northern Syria. It ended in 64 B.C . when Pompey made Syria a Roman province.