What was the language of administration under Delhi Sultanate?

Hint: There are many sources like inscriptions, architecture and coins that provide a lot of information about the Delhi sultanate. There were multiple languages used under the Delhi sultanate. With the introduction of Turkish rulers to India, it influenced and introduced many new languages.

Complete answer: Delhi Sultanate controlled the vast areas of Delhi and laid its foundation at the beginning of the 13th century. The Delhi Sultan built many cities in the area that we know as Delhi. Tarikh or Twarikh; the valuable histories were written in Persian which was the language of administration under the Delhi Sultans. The authors of tawarikh were learned men; administrators and poets. They were asked to recount events and advised rulers on governance and the importance of the just rule. The Delhi sultanate literature originated with the rise of Turkish rulers to the throne which also resulted in the spread of Persian language in India. Soon it became the official language of literary works. However, Sanskrit and other regional languages were also used by people. A centre was opened at Mithila for Sanskrit learning, but the language was under shadowed by Persian. With the Turkish conquest in the Delhi Sultanate, Persian became the court language. It is also believed that many Sanskrit works were also translated into Arabic and Urdu language which also originated during the Sultanate period.

Note: Apart from Persian, Urdu was also developed decisively during the period of Delhi Sultanate. With the expansion of Delhi Sultanate to the South and Deccan plateau, the literary languages were influenced by other languages such as Punjabi, Haryanvi and Urdu.