The decline of ancient Egyptian religion is largely attributed to the spread of Christianity in Egypt. Its strict monotheistic nature did not allow the syncretism seen between ancient Egyptian religion and other polytheistic religions, such as that of the Romans. Although religious practices within Egypt stayed relatively constant despite contact with the greater Mediterranean world, such as with the Assyrians, Persians, Greeks, and Romans, Christianity directly competed with the native religion. Even before the Edict of Milan in AD 313, which legalised Christianity in the Roman Empire, Egypt became an early centre of Christianity, especially in Alexandria where numerous influential Christian writers of antiquity such as Origen and Clement of Alexandria lived much of their lives, and native Egyptian religion may have put up little resistance to the permeation of Christianity into the province. Background Egyptian religion during the Pharaonic era had its roots in prehistory. For a period of nearly three millennia, Egypt largely assimilated any conquerors or invaders from outside of the country who entered. Rulers who came from outside, such as the Hyksos, did not have a significant impact either genetically or culturally, and state support of Egyptian religion rendered it essentially stable throughout the country's ancient history. Specific towns and areas of Egypt usually placed varying emphasis on different gods, and most temples were dedicated to a specific god. This behaviour has led to Egyptian religion being labelled as more of a cult system than a completely homogeneous religion, but regardless, religion played a critical role in the life of every Egyptian. History Late Period The establishment of the Twenty-sixth Dynasty of Egypt in 664 BC is traditionally considered to mark the beginning of the Egyptian Late Period. This era, lasting from 664 BC to 332 BC (the deposition of the final native pharaoh, Nectanebo II), apparently consisted of somewhat of a renewal of Egyptian culture, nationalism, and religion. Though Egypt experienced two separate invasions by the Achaemenid Empire, Persian rulers such as Cambyses II and Darius I respected Egyptian culture and religion and made no attempts to suppress it. Though Herodotus describes the Persian rule of Egypt as tyrannical and oppressive, and this is partly supported by the conscription of Egyptians into the Persian army and some slavery by the Persian upper classes, religious practices specifically did not suffer. Egyptian admiral Wedjahor-Resne, serving under Cambyses, records in his autobiography that Cambyses respected tradition and observance