Most Somalis are Muslims, the majority belonging to the Sunni branch of Islam and the Shafi'i school of Islamic jurisprudence, although some are adherents of the Shia Muslim denomination. Sufism, the mystical dimension of Islam, is also well-established, with many local jama'a (zawiya) or congregations of the various tariiqa or Sufi orders. The constitution of Somalia likewise defines Islam as the state religion of the Federal Republic of Somalia, and Islamic sharia as the basic source for national legislation. It also stipulates that no law that is inconsistent with the basic tenets of Shari'a can be enacted.
Islam entered the region very early on, as a group of persecuted Muslims had, at Prophet Muhammad's urging, sought refuge across the Red Sea in the Horn of Africa. Islam may thus have been introduced into Somalia well before the faith even took root in its place of origin.
In addition, the Somali community has produced numerous important Islamic figures over the centuries, many of whom have significantly shaped the course of Muslim learning and practice in the Horn of Africa, the Arabian Peninsula, and well beyond. Among these Islamic scholars is the 14th century Somali theologian and jurist Uthman bin Ali Zayla'i of Zeila, who wrote the single most authoritative text on the Hanafi school of Islam, consisting of four volumes known as the Tabayin al-Haqa’iq li Sharh Kanz al-Daqa’iq.
Christianity is a minority religion in Somalia, with no more than 1,000 practitioners (about 0.01% of the population). According to estimates of the Diocese of Mogadishu (the territory of which coincides with the country) there were only about 100 Catholic practitioners in Somalia in 2004.
In 1913, during the early part of the colonial era, there were virtually no Christians in the Somali territories, with only about 100–200 followers coming from the schools and orphanages of the few Catholic missions in the British Somaliland
