The modern history of Yemen began with the withdrawal of the Ottoman Empire. In 1839 the British set up a protective area around the southern port of Aden and in 1918 the northern Kingdom of Yemen gained independence from the Ottoman Empire. North Yemen became a republic in 1962, but it was not until 1967 that the British Empire withdrew from what became South Yemen. In 1970, the southern government adopted a communist governmental system. The two countries were formally united as the Republic of Yemen on May 22, 1990.
North Yemen
Mutawakkilite Kingdom of Yemen
Ottoman suzerainty was re-established in northern Yemen in the late 19th century but its control was largely confined to cities, and the Zaidi imam's rule over Upper Yemen was formally recognized. Turkish forces withdrew in 1918, and Imam Yahya Muhammad strengthened his control over northern Yemen creating the Mutawakkilite Kingdom of Yemen. Yemen became a member of the Arab League in 1945 and the United Nations in 1947.
Imam Yahya died during an unsuccessful coup attempt in 1948, and was succeeded by his son Ahmad. Ahmad bin Yahya's reign was marked by growing repression, renewed friction with the United Kingdom over the British presence in the south, and growing pressures to support the Arab nationalist objectives of Egyptian President Gamal Abdul Nasser. He died in September 1962.
Yemen Arab Republic
Shortly after assuming power in 1962, Ahmad's son, the Crown Prince Muhammad al-Badr was deposed by revolutionary forces, who took control of Sana'a and created the Yemen Arab Republic (YAR). Egypt assisted the YAR with troops and supplies to combat forces loyal to the Kingdom. Saudi Arabia and Jordan supported Badr's royalist forces to oppose the newly formed republic starting the North Yemen Civil War. Conflict continued periodically until 1967 when Egyptian troops were withdrawn. By 1968, following a final royalist siege of Sana'a, most of the opposing leaders reached a reconciliation and Saudi Arabia recognized the Republic in 1970.
South Yemen
British domain, Colony of Aden and Aden protectorate
British interests in the area which would later become South Yemen, began to grow when in 1839, British East India Company forces captured the port of Aden, to provide a coaling station for ships en route to India. The colony, known as the Aden Settlement, gained much political and strategic importance after the opening of the Suez Canal in 1869.
Aden was ruled as part of British India until 1937, when the city of Aden became the Colony of Aden, a crown colony in its own right. The Aden hinterland and Hadhramaut to the east formed the remainder of what would become South Yemen and was not administered directly by Aden but were tied to Britain by treaties of protection. Starting in the latter decades of the 19th century and continuing into the 20th century, Britain signed agreements with local rulers of traditional polities that, together, became known as the Aden Protectorate. The area was divided into numerous sultanates, emirates, and sheikhdoms, and was divided for administrative purposes into the East Aden Protectorate and the West Aden Protectorate. The eastern protectorate consisted of the three Hadhramaut states (Qu'aiti State of Shihr and Mukalla, Kathiri State of Seiyun, Mahra Sultanate of Qishn and Socotra) with the remaining states comprising the west. Economic development was largely centred in Aden, and while the city flourished partly due to the discovery of crude oil on the Arabian Peninsula in the 1930s, the states of the Aden Protectorate stagnated.
Encouraged by the rhetoric of President Nasser of Egypt against British colonial rule in the Middle East, pressure for the British to leave grew. Following Nasser's creation of the United Arab Republic, attempts to incorporate Yemen in turn threatened Aden and the Protectorate. To counter this, the British attempted to unite the various states under its protection and, on 11 February 1959, six of the West Aden Protectorate states formed the Federation of Arab Emirates of the South to which nine other states were subsequently added. During the 1960s, the British sought to incorporate all of the Aden Protectorate territories into the Federation. On 18 January 1963, the Colony of Aden was incorporated against the wishes of much of the city's populace as the State of Aden and the Federation was renamed the Federation of South Arabia. Several more states subsequently joined the Federation and the remaining states that declined to join, mainly in Hadhramaut, formed the Protectorate of South Arabia.
