On Nov. 23, 1971, the People’s Republic of China was seated in the United Nations Security Council.

In 1980, an estimated 2,500 to 3,000 people were killed by a series of earthquakes that devastated southern Italy.

In 1996, a commandeered Ethiopian Airlines Boeing 767 crashed into the water off the Comoro Islands, killing 125 of the 175 people on board, including all three hijackers.

In 2005, Ellen Johnson Sirleaf was elected president of Liberia, becoming the first woman to lead an African country.

In 2008, the U.S. government unveiled a plan to rescue Citigroup, injecting a fresh $20 billion into the firm as well as guaranteeing hundreds of billions of dollars in risky assets.

In 2011, Yemen’s President Ali Abdullah Saleh agreed to step down amid a fierce uprising to oust him after 33 years in power.