The British occupation and colonization of southern Yemen (Aden) continued until the late 1950s, when the United Kingdom promised to grant independence to the six states under its control in the south.
Two southern Yemeni groups, the Front for the Liberation of Occupied South Yemen (FLOSY) and the National Liberation Front (NLF), fought the plans as well as each other, forcing the British to declare in 1967 that they would hand over power to any group that could set up a government. In November 1967 the last British troops were withdrawn, and the NLF formed a government with Aden as its capital.
The federation was officially called the People’s Democratic Republic of Yemen (PDRY). The name reflected the Marxist leanings of the government. Other communist countries, including the Soviet Union, China, and Cuba, provided the impoverished nation with economic aid and assistance.
In 1962 the ruling religious leader (imam) in northern Yemen, Imam Ahmad, was overthrown by military officers with the support of Egypt. Fighting ensued between the royalists, supported by Saudi Arabia, and the republicans, supported by Egypt.
Following their defeat in the 1967 Arab-Israeli War, the Egyptians were forced to withdraw their troops. The republicans forged a peace with the remaining royalist tribes and obtained backing from the Saudis.
The fighting ended in 1970, and a government was formed of both royalists and republicans as the Yemen Arab Republic (YAR), known as North Yemen or Yemen, with Sanaa as the capital. The republicans eventually took over the reins of government, exiling the imam’s son to Britain.
In 1972 the two Yemeni governments fought over their common border. The dispute was mediated by the Arab League and resulted in the surprising Cairo Treaty, which anticipated the unification of the two sides within 12 months. The merger was delayed, and the two sides moved further right and left. The late 1970s was a period of assassination of leaders, upheaval, and armed clashes between the two sides.
During the 1980s a trend emerged: The two Yemens would fight, they would sign an agreement to unify the country, and the proposed merger would fail. In addition, in the mid-1980s oil was discovered in the Rub Al-Khali, the desert that straddled the two Yemens. In May 1988 the two Yemens agreed on a neutral zone so that each could use the oil in cooperation with the other.
The resolution of this issue and the boost to their economies helped to pave the way for a concrete 14-month plan for unification. Declining assistance from the crumbling Soviet bloc also encouraged the south to take reunification plans more seriously.
In 1990 the border was demilitarized, and currencies were made valid in both Yemens. On May 22, 1990, the two Yemens were united as the Republic of Yemen, with the political capital in Sanaa and the economic capital in Aden. A referendum ratified the unification, and generally fair and open elections were held in April 1993.
Despite these political developments, the unification was seen by some Yemenis as too favorable to the north. During the 1990–91 Gulf crisis, Yemen declared its support for an Arab solution to the invasion of Kuwait, demanding the Iraqis leave Kuwait and the U.S. troops withdraw from the region.
In retaliation, Saudi Arabia expelled tens of thousands of Yemeni workers. Income plummeted as unemployment rose. In early 1994 violence spread and a new civil war broke out. With no outside support, the south was soon overrun.
After the 1994 war, Yemeni unity was reinforced, and all national parties now support national unity. In 1997 a second fair and calm parliamentary election was held, and President Ali Abdullah Saleh was elected to a seven-year term.
With wide executive powers he appointed a vice president, cabinet members, a prime minister, and the 111 members of the Shura Council. However, the regime is threatened by mounting pressure from Islamist groups and local leaders.