TIMELINE: Pakistan President Musharraf's highs and lows

(Reuters) - Pakistan President Pervez Musharraf imposed emergency rule on Saturday in a bid to reassert his flagging authority against challenges from Islamist militants, a hostile judiciary and political rivals.

Here are some main events in his political career:

October 7, 1998 - Prime Minister Nawaz Sharif appoints General Musharraf army chief but their relationship breaks down over the Kargil border conflict with India the next year.

October 13, 1999 - Musharraf takes power following a bloodless coup after Sharif sacked Musharraf a day earlier while the general was on his way back from Sri Lanka. The country was virtually bankrupt and the coup was relatively popular. Sharif is sent into exile a year later.

June 20, 2001 - Musharraf is sworn in as president but retains his army chief post.

September 12, 2001 - A day after al Qaeda attacked the United States, U.S. Secretary of State Colin Powell tells Musharraf: "you are either with us or against us". A week later, Musharraf announces Pakistan has joined the U.S.-led war on terrorism.

April 30, 2002 - Musharraf wins a controversial referendum on extending his rule for five more years.

July 6, 2002 - Musharraf imposes laws effectively barring former prime ministers Benazir Bhutto and Sharif from power.

December 14 and 25, 2003 - Musharraf survives two al Qaeda inspired assassination attempts in Rawalpindi. Low-ranking army and air force personnel are implicated in the first attack.