The Sasanian king Yazdegerd II passed an edict requiring all the Christians in his empire to convert to Mazdaism, fearing that Christians might ally with Roman Empire, which had recently adopted Christianity. This led to rebellion of Albanians, along with Armenians and Iberians. However, the Albanian king Vache, a relative of Yazdegerd II, converted to the official religion of the Sassanian empire, but quickly reverted to Christianity.