Alexander the Great extended the conquests of his father Philip II of Macedon. His greatest deed was the conquest of the Persian Empire, which until that time had been the single most powerful kingdom in the region. He solidified and extended his father's conquests in Greece, and conquered Egypt, another rich and large kingdom. He extended his conquests all the way into India. As Macedonia was a relatively small and poor country, the military prowess involved in this was quite extraordinary. The Macedonian conquests also imposed Greek on the Macedonian conquests, leading to Greek becoming the elite language used in most business and official dealings in the eastern Rome Empire from Alexander to the fall of Macedonia, and Greek paideia dominating the cultural life of the eastern Roman empire. The main three successor states were the Ptolemies (Egypt), Seleucids (Persia) and series of leaders in Greece and Macedonia.