Delhi became the capital city after the establishment of the Delhi Sultanate in the 13th century. From 1206 to 1526, Delhi was ruled by many rulers of different Muslim dynasties. They all preferred the title of Sultan, and so this period of history came to be known as the Delhi Sultanate.
It started with the Mamluk Dynasty, and was followed by the Khilji, Tughluq, Sayyid and Lodi dynasties.
The Rajput Dynasties ruled Delhi from the early 12th century to 1165 AD.
After Qutbuddin Aybak, his son-in-law Shamsuddin Iltutmish took over the throne of Delhi. Raziyya was the only woman ruler from the Delhi Sultanate to rule Delhi.
Delhi went under the control of the Khilji Dynasty in 1287. The first ruler from the Khilji Dynasty was Jalaluddin Khilji. In 1316, the death of Alauddin Khilji brought the end of the Khilji Dynasty. The Khilji dynasty ruled over Delhi from 1290 to 1320 AD.
The Tughluqs came next. Ghiyasuddin Tughluq was the first emperor of the Tughluq Dynasty. The Tughluq dynasty ruled over Delhi from 1320 to 1414.
Khizr Khan founded the Sayyid dynasty, which ruled over Delhi from 1414 to 1451 AD. Bahlul Lodi established the Lodi Dynasty in 1451. The Lodi dynasty ruled over Delhi from 1451 to 1526.