On 30 October 1918, following the collapse of the Ottoman Empire, Imam Yahya Muhammad of the al-Qasimi dynasty declared northern Yemen an independent state. In 1926, Imam Yahya declared himself king of the Mutawakkilite Kingdom of Yemen, becoming a temporal as well as a (Zaydi) spiritual leader, and won international recognition for the state. In the 1920s, Yahya had expanded Yemeni power to the north into southern Tihamah and southern 'Asir but collided with the rising influence of the Saudi king of Nejd and Hejaz, Abdul Aziz ibn Sa'ud. In the early 1930s, Saudi forces retook much of these gains before withdrawing from some of the area, including the southern Tihamah city of Al Hudaydah. The present-day boundary with Saudi Arabia was established by the 20 May 1934 Treaty of Taif, following the Saudi-Yemeni War of 1934. Yahya's non-recognition of his kingdom's southern boundary with the British Aden Protectorate (later the People's Democratic Republic of Yemen) that had been negotiated by his Ottoman predecessors resulted in occasional clashes with the British.

Yemen became a founding member of the Arab League in 1945 and the United Nations on 30 September 1947. Imam Yahya died during a coup in 1948 and was succeeded by a firm heir. Yahya's son, Ahmad bin Yahya, regained power several months later. His reign was marked by growing development, openness and renewed friction with the United Kingdom over the British presence in the south that stood in the way of his aspirations for the creation of Greater Yemen. In March 1955, a coup by a group of officers and two of Ahmad's brothers briefly deposed the king but was quickly suppressed. Imam Ahmad faced growing pressures to support the Arab nationalist objectives of Egyptian President Gamal Abdul Nasser and, in April 1956, he signed a mutual defense pact with Egypt. In 1958, Yemen joined the United Arab Republic (Egypt and Syria) in a loose confederation known as the United Arab States but it was dissolved in September 1961 and relations between the United Arab Republic (Egypt) and Yemen subsequently deteriorated.

Ahmad died in September 1962, and was succeeded by his son, the Crown Prince Muhammad al-Badr; however, Muhammad al-Badr's reign was brief. Egyptian-trained military officers inspired by Nasser and led by the commander of the royal guard, Abdullah as-Sallal, deposed him the same year of his coronation, 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 Imamate, while Saudi Arabia and Jordan supported Badr's royalist forces opposing the newly formed republic sparking 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; Saudi Arabia recognized the Republic in 1970. The YAR united with the People's Democratic Republic of Yemen (South Yemen) on May 22, 1990, to form the Republic of Yemen.

History of the Imams and Kings of Yemen

The Imams of Yemen and later the Kings of Yemen were religiously consecrated leaders belonging to the Zaidiyyah branch of Shia Islam. They established a blend of religious and secular rule in parts of Yemen from 897. Their imamate endured under varying circumstances until the republican revolution in 1962. Zaidiyyah theology differed from Ismailis or Twelver Shi'ites by stressing the presence of an active and visible imam as leader. The imam was expected to be knowledgeable in religious sciences, and to prove himself a worthy headman of the community, even in battle if this was necessary. A claimant of the imamate would proclaim a "call" (da'wa), and there were not infrequently more than one claimant The Zaydi imamate in Yemen has its origins in 897, when al-Hadi ila al-Haqq Yahya became the first Zaydi imam (with his seat in Saʿda). His fame as an intellectual as well as a leader led to the invitation to Yemen; there he developed a multitude of policies that eventually became the basic guidelines for the religious as well as political characteristics of Yemeni Zaydism.

Yahya, however, was not able to consolidate his rule in all of Yemen; there were revolts as well as segments of the population that did not accept his pretensions to religio-political rule. Although he did not succeed in establishing any permanent administrative infrastructure, Yahya's descendants became the local aristocracy, and it is from among them that the imams of Yemen were selected for the next one thousand years. Yemen throughout most of that period was only rarely a unified political entity; in fact, what was included within its frontiers varied widely, and it has not been governed consistently or uniformly by any single set of rulers. It existed as a part of a number of different political systems/ruling dynasties between the ninth and sixteenth centuries, after which it became a part of the Ottoman Empire.

After Imam Yahya's death, a multitude of smaller dynasties and families established themselves in the Tihama (the low coastal plain) as well as in the highlands. Among the better known of these are the Sulayhids, the Hatims, the Zuray'ids, and the Yu'firids. It was during this period, when the Fatimid state was influential, that a portion of the population was converted to Ismaʿili Shiʿism. Beginning with the conquest of Yemen by the family of Salah al-Din ibn Ayyub (Saladin) in 1174, a series of dynasties exercised a modicum of control and administration in Yemen for roughly the next 400 years; these are, in chronological sequence, the Ayyubids, from 1173/74 to 1228; the Rasulids, from 1228 to 1454; the Tahirids, from 1454 to 1517; and the Mamluks, from 1517 to 1538, when the Ottoman Empire took the Yemeni Tihama.

During most of this period, the dynasties and their rulers were primarily engaged in familial, regional, and occasionally sectarian disputes. Ironically, the Sunni Rasulids, who eventually concentrated their rule in southern Yemen for precisely that reason, were the dynasty under which the region experienced the greatest economic growth and political stability. Very little is known about the Zaydi imams and their efforts to establish themselves and develop some form of administration (including tax collection), or their success in promoting Zaydi goals during this period. From the available evidence, there was very little continuity and a great deal of competition among the Zaydi families and clans. For example, in a presumably representative two-hundred-year period from the thirteenth to the fifteenth centuries, there appear to have been more than twenty different candidates for the imamate, representing more than ten distinct clans. Eventually, as the Europeans entered the Middle East, specifically the Portuguese and then others in the effort to control the Red Sea trade, Yemen and its Zaydi imams were increasingly unable to maintain their independence. It was not until the ascendancy of Imam Qasim ibn Muhammad and his son al-Mu'ayyad Muhammad in the early seventeenth century that the Zaydi Yemenis were able to resist the Ottoman Empire's forces and become an independent political entity.

Modern History

For the next 44 years North Yemen was ruled by two powerful imams. Imam Yahya ibn Muhammad and his son Ahmad created a king-state there much as the kings of England and France had done centuries earlier. The two imams strengthened the state and secured its borders. They used the imamate to insulate Yemen and revitalize its Islamic culture and society at a time when traditional societies around the world were declining under imperial rule. While Yemen under the two imams seemed almost frozen in time, a small but increasing number of Yemenis became aware of the contrast between an autocratic society they saw as stagnant and the political and economic modernization occurring in other parts of the world. This produced an important chain of events: the birth of the nationalist Free Yemeni Movement in the mid-1940s, an aborted 1948 revolution in which Imam Yahya was killed, a failed 1955 coup against Imam Ahmad, and finally, the 1962 revolution in which the imam was deposed by a group of nationalist officers and the Yemen Arab Republic (YAR) was proclaimed under the leadership of Abdullah al-Sallal.

The first five years of President Al-Sallal's rule, from 1962 to 1967, comprised the first chapter in the history of North Yemen. Marked by the revolution that began it, this period witnessed a lengthy civil war between Yemeni republican forces, based in the cities and supported by Egypt, and the royalist supporters of the deposed imam, backed by Saudi Arabia and Jordan. In 1965 Egyptian president Gamal Abdel Nasser met with King Faisal of Saudi Arabia to consider a possible settlement to the civil war. The meeting resulted in an agreement whereby both countries pledged to end their involvement and allow the people of North Yemen to choose their own government. Subsequent peace conferences were ineffectual, however, and fighting flared up again in 1966. By 1967 the war had reached a stalemate, and the republicans had split into opposing factions concerning relations with Egypt and Saudi Arabia. In late 1967 Al-Sallal's government was overthrown and he was replaced as president by Abdul Rahman al-Iryani. Fighting continued until 1970, when Saudi Arabia halted its aid to royalists and established diplomatic ties with North Yemen. Al-Iryani effected the long-sought truce between republican and royalist forces, and presided over the adoption of a democratic constitution in 1970.

In June 1974 military officers led by Colonel Ibrahim al-Hamdi staged a bloodless coup, claiming that the government of Al-Iryani had become ineffective. The constitution was suspended, and executive power was vested in a command council, dominated by the military. Al-Hamdi chaired the council and attempted to strengthen and restructure politics in North Yemen. Al-Hamdi was assassinated in 1977, and his successor, former Chief of Staff Ahmed Hussein al-Ghashmi, was killed in June 1978. The lengthy tenure of President Ali Abdullah Saleh, who ruled North Yemen from 1978 until it merged with South Yemen in 1990, proved more stable. Saleh strengthened the political system, while an influx of foreign aid and the discovery of oil in North Yemen held out the prospect of economic expansion and development.

House of Rassids

In 893 al-Hadi Yahya bin al-Hussain bin al-Qasim ar-Rassi (a descendant of Imam al-Hasan), was invited from Medina to the Northern Highlands of Yemen as an arbiter between the local tribes. Later with the help of the Hamdan tribes of Hashid and Bakil, al-Hadi Yahya bin al-Hussain bin al-Qasim ar-Rassi founded the Zaidi Imamate of Yemen at Sa'da, in 893-7 C.E. He made Zaidi Islam the state religion. He died in 911, and the state he had created crumbled after the death of his able son an-Nasir Ahmad in 934. After the 10th century, succession to the imamate tended not to be hereditary, but circulated among various Sayyid branches. Most, though not all, Imams were descended from al-Hadi Yahya or his grandfather al-Qasim ar-Rassi (d. 860). The term Rassids usually refers to the Imams of the medieval period, up to the 16th century, the later ones being known as Qasimids (Al al-Qasimi). 

Titles and Styles of the Family

Sovereign: Imam and Commander of the Faithful, and King of the Mutawakkilite Kingdom of the Yemen, with the appellation of His Majesty. sons of the Sovereign: Amir (personal name) bin (father's personal name) Hamidaddin, Saif Al-Islam, Prince with the style of His Royal Highness. wives of the sons of the Sovereign: Amira (personal name) bint (father's personal name), Princess with the style of Her Royal Highness. daughters of the Sovereign: Amira (personal name) bint (father's personal name) Hamidaddin, Princess with the style of Her Royal Highness.

List of Imams and Kings of Yemen