The Persians are industrious and scientific. They start the game with Masonry and Bronze Working and build Persian Immortals instead of swordsmen. The term Persia has been used for centuries, chiefly in the West, to designate a region of southern Iran formerly known as Persis or Parsa; the name of the Indo-European nomadic people who migrated into the region about 1000 BC, eventually supplanting the Assyrians and Chaldeans. The first mention of the Parsa occurs in the annals of Shalmanesar III, an Assyrian king, in 844 BC. Cyrus II (559-529 BC), heir to a long line of ruling chiefs in Mesopotamia, was a tolerant and venerated monarch, called the father of his people by the ancient Persians. After a successful revolt against his Achaemenian overlords in 550 BC and inheriting the kingdom of the Medes, Cyrus consolidated his rule on the Iranian Plateau and extended it westward across Asia Minor. In October 539 BC, Babylon, the greatest city of the ancient world, fell to his Persian forces. Following the death of Cyrus' heir, Darius I (522-486 BC), a leading general and one of the princes of the Achaemenid family, proclaimed himself king following suppression of a number of provincial rebellions and challenges from other pretenders to the throne. Darius was in the mold of Cyrus the Great - a powerful personality and a dynamic ruler. To consolidate his accession, Darius I founded his new capital of Parsa, known to the Greeks as Persepolis ("Persian City") and expanded the ranks of his personal bodyguard, the Immortals. Although Darius consolidated and added to the conquests of his predecessors, it was as an administrator that he made his greatest contribution to Persian history. During his reign, political and legal reforms revitalized the provinces and ambitious projects were undertaken to promote imperial trade and commerce: coinage, weights and measures were standardized, and new land and sea routes explored and established. Such activities, however, did not prevent Darius from following an active expansionist policy. Campaigns in the east confirmed gains made by Cyrus the Great and added large sections of the northern