Under the Achaemenids, the "Iranization" of Asia Minor had been significant, and a large Iranian presence had been established in western Asia Minor, Pontus and Cappadocia. Ariarathes had been satrap of Cappadocia for 19 years and a loyal supporter of the Achaemenid kings. By blood, he was related to the ruling Achaemenid house ("Cyrus and Darius’ Seven") as well as other satraps. When Alexander of Macedon invaded Cappadocia as part of his conquest of the Persian Empire, he appointed two temporary governors. For the Iranians in Asia Minor, "as perhaps everywhere", the fall of the Achaemenids "meant crisis". With the victory of Alexander and the emergence of Hellenistic successor kings, the Iranians in Caria and "probably throughout western Asia Minor" eventually started to adapt themselves to the changing situation. The Iranian presence to the west of the Halys River thus slowly started to fade. However, to east of the Halys River, things went differently. The Cappadocians had shown opposition to the invading Macedonians "from the beginning". After the defense of Halicarnassus, the Cappadocians participated in the Battle of Gaugamela (331 BCE) against Alexander, and even after the battle, they "rose up in his rear".