It was not until an 1868 maritime agreement that Qatar was recognized as a sovereign entity by the British, who controlled much of the Persian Gulf. The mid-1800s saw the emergence of a centralized seat of power under the House of Al Thani. However, until the signing of the 1868 agreement, ownership of Qatar switched hands often between the House of Al Thani, the Saudis and the House of Al Khalifa.[7]