1.  History of Yemen   [By www.fact-archive.com]

Islam was introduced into the region in about 630 when Prophet Muhammad was still alive. It was during this period that the mosques in al Janad and the great mosque in Sanaá were built. Virtually all citizens in Yemen today are Muslims, either of the Zaydi order of Shi'a Islam or the Shafi'i order of Sunni Islam, representing approximately 35 percent and 65 percent of the total population, respectively. There are also a few thousand Ismaili Muslims, mostly in the north.

2.Yemen Info
  [By U.S. Library Of Congress]

Religion: Virtually all of Yemen’s citizens are Muslims; approximately 30 percent belong to the Zaydi sect of Shia Islam, and about 70 percent follow the Shafii school of Sunni Islam. A few thousand Ismaili Muslims, who adhere to Shia Islam, live in northern Yemen. Fewer than 500 Jews (a fraction of the former population) also live in the northern part of the country.

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