Excerpts from Books and Wikipedia
"Alexander's empire broke up shortly after his death, and Alexander's general, Seleucus I Nicator, tried to take control of Persia, Mesopotamia, and later Syria and Asia Minor. His ruling family is known as the Seleucid Dynasty. However he was killed in 281 BC by Ptolemy Keraunos. Greek language, philosophy, and art came with the colonists. During the Seleucid Dynasty throughout Alexander's former empire, Greek became the common tongue of diplomacy and literature. Overland trade brought about some fascinating cultural exchanges. Buddhism came in from India, while Zoroastrianism travelled west to influence Judaism. Incredible statues of the Buddha in classical Greek styles have been found in Persia and Afghanistan, illustrating the mix of cultures that occurred around this time." [Wikipedia]