The document provides background information on the rulers of Delhi from the 12th century to the late 15th century. It begins with the Tomara and Chauhan Rajput dynasties in the early 12th century and discusses how Delhi became an important commercial center under their rule. It then outlines the establishment and rulers of the Delhi Sultanate from the early 13th century, including the Slave, Khalji, Tughluq, Sayyid and Lodi dynasties. The document also discusses how tarikh, or Persian histories written by court officials and poets, provide valuable information about the Delhi Sultans, though they reflected the perspectives of urban elites.