In the Delhi Sultanate, the department called 'Diwan-i-Insha' dealt with:

In the Delhi Sultanate, the "Diwan-i-Insha" was the department that dealt with royal correspondence, that is, the drafting and dispatch of the Sultan's letters and orders.

About the Diwan-i-Insha:

• It was headed by an official called the "Dabir-i-Khas" (or Dabir-i-Mumalik).
• It was staffed by "dabirs" (writers or secretaries), who were skilled in writing letters in elegant Persian.
• It handled all the formal and confidential correspondence between the Sultan and other rulers, governors, nobles and officials.
• It drafted the royal orders (farmans) and the letters to be sent to foreign rulers.
• It also kept records of the correspondence.
• It was regarded as one of the four main departments (diwans) of the central government.

The central administration of the Delhi Sultanate:

• The Sultan was the head of the state, the army and the administration.
• He was assisted by several ministers.
• Separate departments handled finance, the army, religious affairs and correspondence, each under its own minister.
• "Diwan-i-Risalat": the department of religious affairs and appeals (or foreign affairs, according to some scholars), headed by the Sadr-us-Sudur.
• "Diwan-i-Insha": the department of royal correspondence, headed by the Dabir-i-Khas.

Other officials:

The "Qazi-ul-Quzat" was the chief judge.

Insha literature:

• The letters were written in a highly polished style, following set rules of composition.
• Collections of letters ("insha") became an important type of Persian literature, and are useful historical sources.

Under the Mughals:

A similar department of correspondence existed, and Abul Fazl wrote the famous "Insha-i-Abul Fazl" (Maktubat-i-Allami), a collection of Akbar's letters.

Why not the other options?

• ✗Military affairs, religious affairs and finance were handled by other departments.