Kuwait City was founded by the clan of al-Sabah. The region was part of the Ottoman Empire at that time, although one of little interest due to its peripheral setting. Over the following decades Sabah I erected a sheikdom in Kuwait that was largely independent from the Turks. In the 19th century the geopolitical situation changed. From a peripheral zone Kuwait became a strategically important territory on the Persian Gulf. The Turks tried to reestablish their control over the land, which was why in 1899 the sheik placed Kuwait under British protection. After the collapse of the Ottoman Empire in World War I, Kuwait became an "independent sheikhdom under British protectorate." In 1938 the first petroleum was found and Kuwait developed into one of the largest producers of oil on the Persian Gulf. Despite of this, Great Britain gave Kuwait its independence in 1961. This sovereignty was disputed by Iraq, however, which claimed the territory of Kuwait for itself. To impede an Iraqi invasion British troops entered Kuwait in 1961, to later be replaced by Arabic soldiers. In 1990 Iraq invaded Kuwait nevertheless, but freed a year later by a coalition led by the US of America. It was one of the beginnings of yonder vicious circle that lead in 2003 to the war in Iraq.