When the vast empire of Alexander the Great broke up, the Macedonian general Seleucus secured the lion’s share for himself and went on to become the longest-lived of Alexander’s successors. His tactical skills and his military innovations – including his use of war elephants on a scale never seen before in the West – earned him the epithet Nicator, “victorious”. When he died at the hands of an assassin in 281 BC, Seleucus ruled over a larger territory than any Hellenistic monarch before or since his time, stretching from the Mediterranean to the Indian Ocean. This book is a study of his life and achievements, his time and his legacy. It is based on Graeco-Roman and Babylonian written sources as well as on the rapidly growing body of archaeological evidence.