Ali Abdullah Saleh (21 March 1947 – 4 December 2017) was a Yemeni military officer and politician who served as the first president of the Republic of Yemen from the Yemeni unification in 1990 until his resignation in 2012, following the Yemeni revolution. Previously, he had served as the fifth and last President of the Yemen Arab Republic (North Yemen), from July 1978 to 22 May 1990, after the assassination of President Ahmad al-Ghashmi. al-Ghashmi had earlier appointed Saleh as military governor in Taiz.
A veteran and officer of the North Yemen civil war, Saleh consolidated power and restored civilian rule after al-Ghashmi's assassination in 1978. Despite military defeat against South Yemen in the Second Yemenite War, a rebellion, and multiple coup attempts, Saleh, though challenged with stagnant economic growth and significant poverty, had managed to bring stability to North Yemen by the mid 1980's, and enjoyed support from both the United States and the Soviet Union. After South Yemen had become unstable following the 1986 crisis and the fall of communism, Saleh achieved reunification as President of the new Republic of Yemen, sharing power in tandem with South Yemen's last leader and transitional Vice President Ali Salem al-Beidh, prominent general Mohsen al-Ahmar and tribal Sheikh and leader of the Islamist Islah movement, Abdullah al-Ahmar, through a Presidential Council. Due to apparent North–South divisions, al-Beidh left the Council in 1993, and in the brief civil war that followed, Saleh's forces, assisted by jihadists such as the Egyptian Islamic Jihad, roundly defeated Southern forces in July 1994.
From 1994 onward, Saleh returned to autocratic rule through rule by decree, and was confirmed by elections in 1999, 2006, and a controversial constitutional referendum in 2001. Until 2011, he presided over stable economic growth and an insurgency by the Ansar Allah movement, commonly known as the Houthis.
As President of unified Yemen, Saleh and the Presidential Council alienated the US and Saudi governments by expressing opposition to the Gulf War, which prompted an exodus of over 800,000 Yemenis from Saudi Arabia, but after Saleh consolidated absolute power, he developed deeper ties with Western powers, especially the United States, during the war on terror. Subsequently, evidence emerged that Islamic terrorism may have been used and encouraged by Saleh in order to win Western support and for disruptive politically motivated attacks. In 2011, in the wake of the Arab Spring, which spread across North Africa and the Middle East (including Yemen), Saleh's time in office became increasingly precarious, until he was eventually ousted as president in 2012. He was succeeded by Abdrabbuh Mansur Hadi, who had been serving as vice president since 1994, and acting president since 2011.