The transcontinental region centered on Western Asia and Egypt. The corresponding adjective is Middle-Eastern and the derived noun is Middle-Easterner. Formerly, the Eurocentric synonym Near East (as opposed to Far East) was commonly used. Arabs, Azeris, Kurds, Persians, and Turks constitute the largest ethnic groups in the region by population, while Armenians, Assyrians, Circassians, Copts, Druze, Jews, Maronites, Somalis, and other ethnic and ethno-religious groups form significant minorities. The History of the Middle East dates back to ancient times, with the (geo-political) importance of the region being recognized for millennia. Several major religions have their origins in the Middle East, including Judaism, Christianity, and Islam; the Baha'i faith, Mandaeism, Unitarian Druze, and numerous other belief systems were also established within the region. The Middle East generally has a hot, arid climate, with several major rivers providing irrigation to support agriculture in limited areas such as the Nile Delta in Egypt, the Tigris and Euphrates watersheds of Mesopotamia, and most of what is known as the Fertile Crescent. Most of the countries that border the Persian Gulf have vast reserves of crude oil, with the dictatorships of the Arabian Peninsula in particular benefiting from petroleum exports. In modern times the Middle East remains a strategically, economically, politically, culturally and religiously sensitive region.