The military history of Yemen remains somewhat nebulous, as major events such as battles lost and won are not easily mapped. As in other Arab countries, skirmishes between shifting tribal factions and the odd coup d’état occurred every now and then. However, a few open armed conflicts in Yemen’s history should be mentioned.
In 1962, revolutionary forces occupied the capital of North Yemen, Sanaa, and declared the Yemen Arab Republic (YAR). Saudi Arabia and Jordan supported the ousted government, Egypt sent troops and combat aircraft to buttress the YAR. In Egypt, the conflict is still referred to as ‘Egypt’s Vietnam’. It is also widely believed that Egypt used mustard gas against royalist troops. Egyptian troops left the country in 1967.
In South Yemen, events reached a boiling point in the 1960s. The British were busy implementing their strategy of abolishing the empire east of Suez. Armed opposition groups such as the National Liberation Front (NLF) were waiting to take over power once the British troops had left. A smooth, peaceful transition was doomed to fail. After the British forces had left the capital Aden in 1967, the NLF took over. In 1969, a Marxist NLF-faction came to power and South Yemen became a Soviet ally.
In 1986, South Yemen’s Prime Minister was ousted by the party leadership in two months of obscure and bloody battles, which cost many thousands their lives. These battles were fought between two wings of the Marxist party, but were largely organized along tribal lines.
The two Yemens merged in 1990, but in reality the unification meant that the south was dominated by the north. On 21 May 1994, southern leaders declared secession, establishing the Democratic Republic of Yemen. However, the DRY was not recognized by the international community. Civil war broke out. Most of the actual fighting in the 1994 civil war occurred in the south of the country, despite air and missile attacks on cities and major installations in the north. Southerners sought support from neighbouring states and received billions of dollars of equipment and financial assistance, mostly from Saudi Arabia, which felt threatened by a united Yemen. The United States strongly supported Yemeni unity, but repeatedly called for a ceasefire and a return to the negotiating table. Various attempts, including by a UN special envoy, were unsuccessful in effecting a ceasefire. Aden was captured on 7 July 1994. Other resistance quickly collapsed and thousands of southern leaders and military went into exile. In the early stages of the fighting, President Ali Abdullah Saleh announced a general amnesty. Most southerners returned to Yemen after a short period of exile.
From 2004 onwards the central government faced an uprising, which turned into a guerrilla, by the Houthis – marginalized northerners, and followers of Hussein Badr Eddin al-Houthi. These wars were increasingly violent and costly, the central government never gaining the upper hand. In 2009, Saudi Arabia intervened and attacked Houthi positions inside Yemen.
After al-Qaeda attacked New York and Washington in September 2001, Yemen received military support and advisors from the United States in order to fight against the group’s substantial presence in the country.