The Republic of Yemen, with a land area of 527,970 sq km (slightly larger than twice the size of Wyoming), is located on the Arabian Peninsula and borders the countries of Saudi Arabia and Oman.
Yemen was one of the oldest centers of civilization in the Near East. Between the 12th century BC and the 6th century AD, it was part of the Minaean, Sabaean, and Himyarite kingdoms. In the 7th century, Islamic caliphs began to exert control over the area. After this caliphate broke up, the former north Yemen came under control of Imams of various dynasties. Egyptian Sunni caliphs occupied much of north Yemen throughout the 11th century. By the 16th century and again in the 19th century, north Yemen was part of the Ottoman Empire.
Ottoman control was largely confined to cities with the Imam's suzerainty over tribal areas formally recognized. Turkish forces withdrew in 1918, and Imam Yahya strengthened his control over north Yemen. Yemen became a member of the Arab league in 1945 and the United Nations in 1947.
British influence increased in the south and eastern portion of Yemen after the British captured the port of Aden in 1839. It was ruled as part of British India until 1937, when Aden was made a crown colony with the remaining land designated as east Aden and west Aden protectorates. By 1965, most of the tribal states within the protectorates and the Aden colony proper had joined to form the British-sponsored federation of south Arabia.
In 1965, two rival nationalist groups--the Front for the Liberation of Occupied South Yemen (FLOSY) and the National Liberation Front (NLF)--turned to terrorism in their struggle to control the country. In 1967, in the face of uncontrollable violence, British troops began withdrawing, federation rule collapsed, and NLF elements took control after eliminating their FLOSY rivals. South Arabia, including Aden, was declared independent on November 30, 1967, and was renamed the People's Republic of South Yemen. In June 1969, a radical wing of the Marxist NLF gained power and changed the country's name on December 1, 1970, to the People's Democratic Republic of Yemen (PDRY). In the PDRY, all political parties were amalgamated into the Yemeni Socialist Party (YSP), which became the only legal party. The PDRY established close ties with the Soviet Union, China, Cuba, and radical Palestinians.
In 1972, the governments of the PDRY and the YAR declared that they approved a future union. However, little progress was made toward unification, and relations were often strained.
In May 1988, the YAR and PDRY governments came to an understanding that considerably reduced tensions including agreement to renew discussions concerning unification, to establish a joint oil exploration area along their undefined border, to demilitarize the border, and to allow Yemenis unrestricted border passage on the basis of only a national identification card.
In November 1989, the leaders of the YAR (Ali Abdullah Saleh) and the PDRY (Ali Salim Al-Bidh) agreed on a draft unity constitution originally drawn up in 1981. The Republic of Yemen (ROY) was declared on May 22, 1990.
CIA World Factbook; U.S. State Department Background Notes, 08/2008; 12/2007