Sheikh Qassim Bin Mohammad Bin Thani was born around 1825. He took the full responsibility of Qatar and he was given the Ottoman title of Qaim-Maqam (Deputy Governor) of Qatar in 1876. Ottoman attempts to increase their power in Qatar by appointing Ottoman official including administrators at Zubara, Doha, Wakrah and Khor al-Udaid and by establishing a Custom House at Doha and strengthening their garrison at Doha led to open war with Sheikh Qassim in March 1893 at al-Wajbah, 15 Kilometers west of Doha. 

In the battle the Ottomans were defeated by Sheikh Qassim and his forces. This Ottoman defeat was a landmark in the modern history of Qatar because of the courage with which Sheikh Qassim and his people faced up the Ottomans. In July 1913, Sheikh Qassim died. The Sheikh is regarded as the founder of Modern Qatar.