Iraq is traversed by the Rivers Tigris and Euphrates, whose valley was the site of the ancient civilizations of Mesopotamia. It was conquered by Arabia in the 7th century and from 1534 formed part of the Ottoman Empire. After the First World War a kingdom was established, although the country was under British administration until 1932. Saddam Hussein came to power as President in 1979. From 1980 to 1988 the country was at war with its eastern neighbour Iran. In 1990 Iraq invaded Kuwait; it was expelled by an international coalition of forces in the Gulf War of 1991. In 2003 the country was invaded and occupied by US-led forces in response to its failure to comply fully with a UN resolution that it should disarm