The Al Qasimi ruling family flag; Ras al-Khaimah and Sharjah, both ruled by the Al Qasimi, have the same flag
Al Qasimi (Al Qassimi; plural: Al Qawasem القواسم) is an Adnani Arabian tribe. The Al Qasimi dynasty are from the Ashraaf; they trace their ancesty from Imam Ali. Today, two branches of the Al Qasimi royal family rule the Emirates of Sharjah and Ras al-Khaimah in the United Arab Emirates. Each Emirate is ruled by an emir (colloquially called "sheikh" as with other emirs in the region).
The Al Qawasem, based at Ras al-Khaimah, emerged as a major maritime power during the eighteenth century. They ruled some of the shores and islands of Persia, like Bandar Lengeh, that were opposite to U.A.E in different eras between (1800—1890). Their control of trade in the Persian Gulf area led to conflict with Oman and eventually with Britain. In 1819, the British defeated Al Qawasem after several naval battles.