1933: Abdul Aziz ibn Saud, founder of modern-day Saudi Arabia, allows first American oil company to begin looking for oil in his kingdom. Large oil deposits are discovered in 1938, but major production doesn't begin until 1945.

1945: President Roosevelt meets with Abdul Aziz on a U.S. warship in the Red Sea to start relations and guarantee oil supplies for the U.S. war effort.

1973: Saudi Arabia and other OPEC nations begin oil embargo against the United States because of their anger over U.S support for Israel.

1991: United States leads coalition to repel Saddam Hussein's Iraqi army from Kuwait and to prevent invasion of Saudi Arabian oil fields. After war, some U.S. troops remain on Saudi soil to patrol flight-interdiction zones.

1996: Members of Saudi Hezbollah dissident group bomb Khobar Towers complex in Dhahran, Saudi Arabia, killing 19 U.S. servicemen. U.S. prosecutors indict 14 people in 2001, some in custody in Saudi Arabia, but Saudi Arabia says it will not allow them to be tried in the United States.