The earliest recorded civilizations of S Arabia were the Minaean and Sabaean. The Sabaean kingdom (see Sheba) flourished from c.750 B.C. to c.115 B.C., with Marib (located east of Sana) the capital after c.600 B.C. Sabaean society was highly developed technically, as witnessed by the remains of a great dam at Marib that was the center of a large irrigation system. The Himyarites, who followed the Sabaeans, were invaded by the Romans (1st cent. B.C.) and were occupied by the Ethiopians (c.A.D. 340–A.D. 378). During the second Himyarite kingdom Christianity and Judaism took root in Yemen. Ethiopia again conquered the country in 525. After a Persian period (575–628), Islam came to Yemen, which was soon reduced to a province of the Muslim caliphate.
After the breakup of the caliphate, Yemen came under the control of the rising Rassite dynasty, imams of the Zaidi sect who built the theocratic political structure of Yemen that lasted until 1962. The Fatamid caliphs of Egypt occupied most of Yemen from c.1000 until c.1175, when it fell to the Ayyubids, who ruled until c.1250. By 1520, Yemen formed part of the Ottoman Empire, which exercised at least nominal sovereignty until the end of World War I. A turbulent wave of Wahhabism, a puritanical sect of Islam, swept across the Arabian peninsula at the opening of the 19th cent. and drove out the Zaidi imams. Ibrahim Pasha of Egypt, acting in the name of the Ottoman sultan, drove out the Wahhabis in 1818, and the Egyptians remained until 1840. The Ottoman Turks then replaced the Egyptians, giving the imam full autonomy in the interior.
After the Ottoman evacuation (1918), Imam Yahya moved to expand Yemen's territory, but his only gain was the port and surrounding area of Hodeida. In 1934, after a brief Saudi Arabian invasion and skirmishes with Great Britain (which had the protectorate of Aden), Yemen's boundaries were fixed by treaty with Saudi Arabia and Great Britain. However, clashes on the Aden border continued sporadically. Modifying its traditional policy of isolation, Yemen became more active in foreign affairs after World War II; it joined the Arab League in 1945 and the United Nations in 1947 and established diplomatic relations with other nations. However, the imam, as both king and spiritual leader, continued to rule along theocratic lines.
Dissatisfaction, hitherto rapidly suppressed, grew, and in 1948 a palace revolt broke out, and the old Imam Yahya was assassinated. Crown Prince Ahmad drove out the insurgents and succeeded as imam. The new ruler accepted technical and economic assistance from both the West and the Communist bloc. From 1958 to 1961, Yemen joined with the United Arab Republic (Egypt and Syria) to form the United Arab States, which in reality was a paper alliance. Disorders broke out in 1959, and Imam Ahmad survived an assassination attempt in 1961. After his death in 1962, Imam Ahmad was succeeded by Crown Prince Muhammad al-Badr (later Imam Mansur Billah Muhammad), who favored a neutralist foreign policy. Soon afterward a revolt headed by pro-Egyptian army officers deposed the imam, but he escaped and led royalist tribes against the new government.
The ruling junta, commanded by Col. Adallah al-Salal, proclaimed a republic, and the army contained the imam's forces. Yemen then became an international battleground, with Egypt supporting the republicans and Saudi Arabia and Jordan the royalists. The Yemeni republicans split into opposing factions on the issue of Egyptian support. In an administrative reorganization in 1966, the independent government of Premier Hassan al-Amri was ousted by a strongly pro-Egyptian regime, with al-Salal assuming the office of premier. Many of al-Amri's supporters were arrested or removed from office. In 1967, by mutual agreement, Egyptian troops were withdrawn from Yemen, and Saudi Arabian aid to the royalists was halted. In Nov., 1967, al-Salal's government was overthrown while he was abroad, and a three-man republican council was formed with Qadi Abd al-Rahman al-Iryani (one of the anti-Egyptian leaders) as chairman; al-Amri resumed the premiership.
Fighting between the republicans and the royalists continued until 1970, when Saudi Arabia formally recognized the republican regime and stopped aid to the royalists. Between 1967 and 1972 frequent border clashes occurred between Yemen and Southern Yemen, until an accord was signed (1972) to merge the two countries. However, by 1974 the agreement had not been implemented, and fighting continued between the two states. On June 12, 1974, Chairman al-Iryani resigned after a period of internal political tension, and the next day a group of army officers led by Col. Ibrahim al-Hamidi staged a nonviolent coup. The officers established a command council to govern the country, suspended the constitution, and reestablished civilian rule.
Al-Hamidi was assassinated in Oct., 1977, and was succeeded by Lt.-Col. Ahmad al-Ghashmi, who continued civilian administration until his assassination in June, 1978. Lt.-Col. Ali Abdullah Saleh then was elected president. In early 1979 border fighting with neighboring Southern Yemen erupted into full-scale war. Peace was soon established, however, and another unification agreement was devised. Saleh was elected to a second term in 1983 and a third term in 1988.
A number of ancient empires, including the Minaean, Sabaean, and Himyarite, flourished in southern Yemen. The region came under Muslim influence in the 7th cent. In the 16th cent. it became part of the Ottoman Empire and came under the suzerainty of the imams of Yemen. (For a more detailed history, see above history of Northern Yemen or see Arabia.)
The British presence in Southern Yemen began in 1839, when forces of the British East India Co. occupied Aden. In 1854 and 1857 the Kuria Muria and Perim islands were ceded to the British, and other mainland areas were purchased by them. Between 1886 and 1914, Britain signed a number of protectorate treaties with local rulers. In 1937 the area, which by then consisted of 24 sultanates, emirates, and sheikhdoms, was designated the Aden Protectorate and was divided for administrative purposes into the East Aden protectorate and the West Aden protectorate. In 1959 six small states of the West Aden protectorate formed the Federation of the Emirates of the South; it was later enlarged to 10 members. Despite considerable opposition from its population, the Aden colony proper was made part of the federation (1963), which was then renamed the Federation of South Arabia (see South Arabia, Federation of).
By 1965, 16 tribal states had joined the federation. However, nationalist groups in Aden remained adamantly opposed to the federation and began a terrorist campaign against the British. Two rival nationalist groups emerged: the National Liberation Front (NLF) and the Front for the Liberation of Occupied South Yemen (FLOSY). Although Britain had promised to withdraw from the region by 1968, the NLF, which had emerged as the dominant group by 1967, forced the collapse of the federation after taking control of the governments of all the component states. Britain accelerated its withdrawal, and Southern Yemen became independent in Nov., 1967, with Qahtan al-Shaabi of the NLF the first president. In June, 1969, he resigned, and was succeeded by Rubayi Ali. In 1970 the country received a new constitution and was renamed the People's Democratic Republic of Yemen.
Following independence border disputes arose with Oman and the Yemen Arab Republic, some of which led to armed clashes. An accord was signed with the Yemen Arab Republic in 1972 calling for the end of fighting and the merger of the two countries. However, the agreement was not to be implemented for several years. In Apr., 1972, the government of Southern Yemen suffered a severe blow when 25 of its top officials were killed in an airplane crash. Rubayi Ali was ousted in June, 1978, by Abdalfattah Ismail, a radical rival who in 1979 signed a 20-year relation treaty with the Soviet Union. Soviet influence, including the presence of naval bases, became predominant in Southern Yemen, which was the Arab world's only Marxist state. Fighting with Northern Yemen again broke out in Feb., 1979, but was resolved one month later by a peace treaty.
In 1983, Ali Nasser Muhammad, Ismail's successor as president, restored relations with Saudi Arabia and Oman. In Jan., 1986, Muhammad tried to eliminate internal party opposition by killing party leaders and former president Ismail, but rival political fighting erupted for two weeks, after which Muhammad fled to Ethiopia. His supporters were mostly eliminated by the administration of Haider Abu Bakr al-Attas, Muhammad's successor. In Oct., 1988, Attas visited Oman, the first Southern Yemen leader to do so.
The leaders of the two Yemens met in Dec., 1989, when final unification agreements were made, and the borders were opened in Feb., 1990. On May 22 of that year, the two Yemens were officially united. North Yemen president Saleh became the leader of a unified Yemen, and Sana became the nation's capital. By 1993, however, relations between north and south had again grown tense. Fighting between northern and southern army units in 1994 erupted into a civil war between southern secessionists and Yemen's northern-based government. The war lasted for nine weeks and was decisively won by northern forces. Subsequently, Saleh was officially elected by parliament as president of the country, and a coalition government that excluded the leading southern party was established. The new government imposed unpopular economic austerity measures. Muslim extremists committed sporadic acts of violence in the south, and armed tribespeople from remote areas staged kidnappings of foreign tourists.
Yemen's armed forces clashed with Eritrea over control of the Hanish Islands in the Red Sea in the early 1990s; the Hague Tribunal awarded the islands to Yemen in 1998. The president's party won nearly two thirds of the seats in the 1997 legislative elections. In Sept., 1999, in Yemen's first direct presidential election, Saleh was returned to office; candidates from opposition parties were not approved to run, and the government was charged with fraudulently inflating the vote count. In Oct., 2000, the U.S.S. Cole was damaged by a suicide bombing while anchored at Aden and the British embassy was bombed. Also in 2000, a border treaty ending disputes with Saudi Arabia that dated to the 1930s was signed.
President Saleh announced support for the U.S. "war on terror" in 2001 and subsequently received American aid and made some moves against Muslim extremists, but the terror attacks also continued. Saleh's General People's Congress won more than two thirds of the seats in the 2003 legislative elections. In June, 2004, government forces began raids against supporters of Shiite cleric Hussein al-Hawthi, who was accused of sedition and extremism. The cleric had denounced the government's pro-American policies and government corruption. Several months of fighting in NW Yemen, in which hundreds died, followed, and in September Sheikh Hawthi was killed and a cease-fire mediated. Fighting erupted again in Apr., 2005, when the government attacked Hawthi's followers after unsuccessful negotiations. Almost a year later some 600 rebels were released in an amnesty, but attacks continued spordically until June, 2007, when a cease-fire was agreed to. There were, however, additional attacks by Jan., 2008, and in subsequent months, and fighting with the rebels intensifed in the second half of 2009, displacing some 200,000 persons. In Nov., 2009, a rebel incursion into Saudi Arabia led also to fighting between Saudi forces and the rebels. The conflict extended into Feb., 2010, when a truce was established; the rebels also withdrew from Saudi Arabia. The truce largely held, although there were clashes in July, 2010. There also have been clashes with Islamic militants linked to Al Qaeda, with an increase in operations against them in E Yemen in early 2010 after an attempted bombing (Dec. 25, 2009) of a plane in the United States by a Nigerian with ties to the Yemeni Islamists.
Meanwhile, in July, 2005, fuel price increases sparked protests and riots across Yemen, leading the government to roll the increases back somewhat. That same month the president said he would not seek a new term in Sept., 2006, a position he reversed a year later. In the 2006 presidential Saleh was reelected with more than three-fourths of the vote, but the opposition rejected the results. Despite irregularities, the election was generally regarded as an improvement over the previous presidential poll.
By early 2008, S Yemeni unhappiness with unification was again becoming pronounced, as protests and riots occurred in parts of S Yemen; sporadic unrest continued into 2010. Amid protests in early 2011 against his rule (which echoed similar protests in Tunisia and Egypt against entrenched rulers there), the president promised in February not to seek reelection. Recurring demonstrations, however, were stoked by the killings of demonstrators, which also split the ruling party and the military. By April, the widespread protests had crippled the country.
The Gulf Cooperation Council (GCC) attempted to negotiate Saleh's resignation, but the president several times reneged on agreements. The unsettled situation invigorated militant Islamists, who mounted attacks in S Yemen and were able to seize control of some areas; fighting with the Islamists continued into 2012. In late May tribal militias became increasing active in opposing Saleh, and fought with government forces in Sana and Taiz. In early June Saleh was severely wounded in an attack on the presidential compound and went to Saudi Arabia for treatment; he returned in September. A truce with the tribal militias largely held during the summer, but beginning in September there were more serious outbreaks.
In November, Saleh agreed to transfer his powers to Vice President Abdrabuh Mansur Hadi under a GCC-brokered plan, remaining on as titular president until an election (later were called for Feb., 2012). An interim government, with cabinet posts divided equally between the government and opposition and headed by Prime Minister Mohammed Basindwa, an opposition politician, was appointed in Dec., 2011; the new government subsequently approved a law granting immunity to Saleh. In Feb., 2012, Abdrabuh Mansur Hadi was elected president in an election in which he was the only candidate, but Saleh remained a political force and attempted to undermine the interim government through his supporters in it and the military. The military subsequently mounted an offensive against the militant Islamists in S Yemen, and by mid-2012 had largely reestablished government control there, but the area continued to be the scene of sporadic fighting.
In August and in December, Hadi ordered armed forces reorganizations designed to reduce the influence of Saleh and others in the military. Not all the changes. however, came into effect in subsequent months. In Apr., 2013, Hadi ordered further changes and removed Saleh's relatives from military command positions. A national dialogue conference intended to help develop a new constitution for Yemen began in Mar., 2013, and ended in Jan., 2014; it approved a federal system for the country and extended Hadi's term by a year. In Sept., 2013, the prime minister was the subject of an assassination attempt. Hawthi Shiites attacked in a Sunni Salafist school in N Yemen in October and November, accusing the Salafists of running a training camp for foreign fighters.