Charles William Ferdinand (German: Karl Wilhelm Ferdinand, Fürst und Herzog von Braunschweig-Wolfenbüttel) (October 9, 1735 – November 10, 1806), Duke of Brunswick-Wolfenbüttel, was a sovereign prince of the Holy Roman Empire, and a professional soldier.

His titles are usually shortened to Duke of Brunswick in English-language source

He succeeds his father as sovereign prince of the Principality of Brunswick-Wolfenbüttel, one of the princely states of the Holy Roman Empire.

He is a recognized master of the modern warfare of the mid-eighteenth century, who succeeds his father as sovereign prince of the Principality of Brunswick-Wolfenbüttel, one of the princely states of the Holy Roman Empire.

He is a cultured and benevolent despot in the model of Frederick the Great, and is married to Princess Augusta, a sister of George III of Great Britain.