Before the 18th century, Aligarh was known as Kol or Koil. The name Kol referred to the entire district. The origin of the name is obscure. In some ancient texts, Kol has been referred to in the sense of a tribe or caste, the name of a place or mountain and the name of a sage or demon. Study of the place-name indicates that the district was once fairly well covered by forests and groves. The history of the district through the 12th century AD is obscure.
According to Edwin T. Atkinson, the name Kol was given to the city by Balarama, who slew the great Asura (demon) Kol there and, with the assistance of the Ahirs, subdued this part of the doab. In another account, Atkinson points out a "legend" that Kol was founded by the Dor tribe of Rajputs in 372 A.D. This is further confirmed by an old fort, the ruined Dor fortress, which lies at the city centre.
Some time before the Muslim invasion, Kol was held by the Dor Rajputs. In the time of Mahmud of Ghazni, the chief of the Dors was Hardatta of Baran. Statues of Buddha and other Buddhist remains have been found in excavations where the citadel of Koil stood, indicating a Buddhist influence. Hindu remains indicate that the citadel probably had a Hindu temple after the Buddhist temple.
In 1194 AD, Qutb-ud-din Aibak marched from Delhi to Kol, "one of the most celebrated fortresses of Hind". Qutb-ud-din Aibak appointed Hisam-ud-din Ulbak as the first Muslim governor of Koil.
Koil is also mentioned in Ibn Battuta's Rihla, when Ibn Battuta along with 15 ambassadors representing Ukhaantu Khan, the Mongol Emperor of the Yuan dynasty in China, travelled to Kol city en route to the coast at Cambay (in Gujarat) in 1341. According to Ibn Battuta, it would appear that the district was then in a very disturbed state since the escort of the Emperor's embassy had to assist in relieving Jalali from an attacking body of Hindus and lost an officer in the fight. Ibn Batuta calls Kol "a fine town surrounded by
