On 20 January 1663, the Diet convened to deal with threats from the Ottoman Empire (the Turkish Question).

[2] Since the Peace of Westphalia in 1648, the Holy Roman Emperor had been formally bound to accept all decisions made by the Diet.

The Emperor was represented by a Principal Commissioner (Prinzipalkommissar), a position that accrued to the Thurn und Taxis family from 1748.

The last action of the Diet, on 25 March 1803, was the passage of the German Mediatisation, which reorganized and secularized the Empire.

[6] Following the approval of that final constitutional document, the Diet never met again and its existence ended with the dissolution of the Empire in 1806.