Timeline: Saleh's 33-year rule in Yemen

A list of important dates in the 33 years since Ali Abdullah Saleh took over then-North Yemen.

Yemen's President Ali Abdullah Saleh 311  (R) (photo credit: REUTERS/Ammar Awad)
Yemen's President Ali Abdullah Saleh 311 (R)
(photo credit: REUTERS/Ammar Awad)
July 1978 - Saleh takes power in then-North Yemen.
February 1979 - Saleh crushes an attempt to overthrow him.
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May 1990 - Pro-Western North Yemen and socialist South Yemen merge after 300 years of separation to form a new republic dominating the strategic entrance to the Red Sea.
July 1994 - North Yemen declares an almost three-month Yemeni civil war over after gaining control of Aden, its southern foe's last bastion.
October 2000 - A US warship, the USS Cole, is attacked in Aden harbour by al Qaida bombers, killing 17 sailors.
November 2001 - Saleh declares support for US President George W. Bush's "war on terror".
February 2008 - Fragile truce is signed with North Yemen's Houthis, a Zaidi Shi'ite tribe, but the four-year revolt soon resumes in the northwest region of Saada. Saleh unilaterally declares war over in July 2008. Full-scale fighting resumes a year later.
January 2009 - Al Qaida's Yemeni and Saudi wings merge in a new group called al Qaida in the Arabian Peninsula (AQAP), led by Nasser al-Wahayshi.
Jan. 29, 2011 - Yemen's ruling party calls for dialogue with the opposition in a bid to stem anti-government protests.
-- Saleh supporters attack and disperse Yemenis who try to march to the Egyptian embassy in Sanaa to express solidarity with Egyptian anti-government demonstrators.
March 2 - The opposition presents Saleh with a plan for a smooth transition of power, offering him a graceful exit.
March 18 - Snipers kill 52 protesters among crowds that flock to a sit-in at Sanaa University after Friday prayers. Saleh declares a state of emergency.
March 20 - Saleh dismisses his government.
March 21 - Senior army commanders, including Saleh ally General Ali Mohsen, commander of the northwest military zone, say they have switched support to pro-democracy activists.
March 23 - Saleh offers to step down by the end of 2011. He also proposes to hold a referendum on a new constitution, then a parliamentary election and presidential vote.
April 23 - Saleh agrees to step down in weeks in return for immunity from prosecution. The opposition agrees to the plan.
April 25 - The opposition agrees to take part in a transitional government under a Gulf-negotiated peace plan.
May 21 - Yemen's opposition signs the transition deal.
May 22 - Five members of the ruling party sign the deal, but Gulf Arab states suspend it after Saleh asks for additional conditions and diplomats fail to persuade him to sign it.
May 24 - Saleh's refusal to sign the power transfer deal sparks street battles in Sanaa between his security forces and the powerful Hashed tribal alliance, led by Sadeq al-Ahmar.
May 30 - A truce between loyalist forces and tribesmen breaks down, with militants loyal to Ahmar regaining control of Yemen's ruling party building in the Hasaba district of Sanaa.
June 3 - Shells strike Saleh's palace in Sanaa, killing seven people and wounding the president, the prime minister, his deputy and the parliament speaker. The attack is blamed by the government on tribesmen.
-- Street battles have killed at least 155 people in the previous 10 days. More than 370 people have been killed since protests started.
June 4 - Saleh flies to Saudi Arabia for treatment after the attack on his palace. Vice president Abd-Rabbu Mansour Hadi becomes acting president.