Practitioners of Islam first entered Somalia in the northwestern city of Zeila during Muhammad's lifetime whereupon they built the Masjid al-Qiblatayn; as such, Islam has been a part of Somali society for 14 centuries. Practicing Islam reinforces distinctions that further set Somalis apart from their immediate neighbors. Sunnism is the strand practiced by 90% of the population. Although Pew Research Center has not conducted a survey in Somalia, its Somali-majority northwestern neighbour Djibouti reported a creed breakdown of Muslims which was reported as 77% adhering to Sunnism, 8% as non-denominational Muslim, 2% as Shia, thirteen percent refusing to answer, and a further report inclusive of Somali Region stipulating 2% adherence to a minority sect (e.g. Ibadism, Quranism etc.). The role of religious functionaries began to shrink in the 1950s and 1960s as some of their legal and educational powers and responsibilities were transferred to secular authorities. The position of religious leaders changed substantially after the 1969 revolution and the introduction of scientific socialism. Siad Barre insisted that his version of socialism was compatible with Qur'anic principles, and he condemned atheism. Religious leaders, however, were warned not to meddle in politics. History Birth of Islam and Middle Ages Islam was introduced to the northern Somali coast early on from the Arabian peninsula, shortly after the hijra. Zeila's two-mihrab Masjid al-Qiblatayn dates to the 7th century, and is the oldest mosque in the city. Somalis were among the earliest non-Arabs to convert to Islam. Not only the earliest non-Arabs, but the religion of Islam in Somali predates almost every single Muslim nation of today. In the late 9th century, Al-Yaqubi wrote that Muslims were living along the northern Somali seaboard. He also mentioned that the Adal kingdom had its capital in the city, suggesting that the Adal Sultanate with Zeila as its headquarters dates back to at least the 9th or 10th century. According to I.M. Lewis, the polity was governed by local Somali dynasties, who also ruled over the similarly-established Sultanate of Mogadishu in the littoral Benadir region to the south. Adal's history from this founding period forth would be characterized by a succession of battles with neighboring Abyssinia. In 1332, the Zeila-based King of Adal was slain in a military campaign aimed at halting the Abyssinian Emperor Amda Seyon I's march toward the city to avenge the slaughtered Christians including a famous monk sent to wage peace and destroyed Churches