He was the second son of Duke Charles III and Claude de France, daughter of King Henry II.

On 23 June 1591 he was appointed apostolic legate for the "Three Bishoprics" (Metz, Verdun and Toul) that fell under French rule.

The local Protestants chose Johann Georg von Brandenburg, while the Catholic canons fled to Saverne.

During his time at Saverne, raising troops for war, his treasury, managed at Paris by Stefano del Poggio, disbursed 15,386 francs.

[3] In September 1593, through the mediation of King Henry IV of France, the bishopric was divided between the contending prelates: seven districts, including Saverne, went to Charles.

In 1603 Charles was confirmed by Clement VIII as the primate of Lorraine with his seat and primatial church in Nancy.