A man who changed Hellenistic world

Do you known who was mister Seleucus? He was man who linked different epochs. He was born on the edge of Ancient Greece, in Macedonia in 358 BC. Then he became a friend and military commander of the most influential man in Ancient Greece, Alexander the Macedon. He was able to look the farthest corder of Ancient World. After Alexander's death he became the ruler of the largest part of ex-Alexander Empire and was active member during war of Diadochi. And eventually he was the key person in Hellenistic world in Asia until 281 BC.