Country occupying the most southwesterly peninsula of the Asiatic continent, including the Sultanate of Nedjed, the Imamate of Yemen, the British Protectorate of Aden, the Principality of Asir, the Hadramaut, the Sultanate of Oman, the Sultanate of Koweyt, and the Emirate of Bahrein; approximate area, 1,250,000 square miles; population almost entirely Muslim. Though Christianity in Arabia dates from Apostolic times, the Arabs, being of a lax and sensual nature, were indifferent in the practise of their religion, fell easily into the heresies of Arianism, Nestorianism, and Monophysitism, and lost all traces of Christianity after the appearance of Islam. Missionary work has been conducted along the outskirts, but the interior of the country is almost impenetrable. The Catholic Church is represented by the Vicariate Apostolic of Arabia, established as a prefecture Apostolic, 1875, erected into the Vicariate Apostolic of Aden, May 4, 1888, and the name changed to Arabia, June 28, 1889. It is entrusted to the Capuchins. See also: