Extensive lands have come under the sway of the Persian Empires throughout history, but the heartland of the Persian culture and Indo-European language is Fars in the mountainous, southwest region of Iran, the historic name derived from the 'Aryan' root. A monotheistic religion based on the teachings of Zoroaster underpinned the governance of Persia which was multi-ethnic. Western history recorded the Persian Empire from Greek and Judeo-Biblical perspectives, introducing Westerners to the history of Darius the Great and his summer capital of Persepolis, and the conquests of Alexander the Great. The Persian Empire stood at the crossroads of the great Silk Routes from China, and trade in luxury goods brought wealth to Persia. Rivalry with Byzantine, Ottoman and European Empires has shaped the history of Iran, while the nation values its ancient heritage within the framework of a modern state in the 21st century.