Who did alexander the great marry to unite his empire?

Alexander III of Macedon, known as Alexander the Great was the son of King Philip II of Macedon. He became king upon his father’s death in 336 BCE and went on to conquer most of the known world of his day. He is known as 'the great' both for his military genius and his diplomatic skills in handling the various populaces of the regions he conquered. He is further recognized for spreading Greek culture, language, and thought from Greece throughout Asia Minor, Egypt, and Mesopotamia to India and thus initiating the era of the "Hellenistic World".

A great website to read in is: http://www.ancient.eu/Alexander_the_Great/