His favourite residences were the Château de Beaumont and Heverlee castle, where he housed his collections and created beautiful gardens.

He was the eldest son of Philippe III de Croÿ, Prince of Chimay, Duke of Aarschot, and Jeanne of Halewijn.

In December 1605, eight months after the death of his first wife, he married his cousin Dorothea of Croÿ, daughter of Charles Philippe de Cröy, Marquis d’Havré (1549–1613).

It constitutes two large volumes still preserved today by the de Croÿ family: one covers property located in Hainaut, the other those lying in Brabant, Flanders, Namur, Artois and Picardy.

They cover a very extensive perimeter, encompassing many areas from the north of present-day France and Belgium, from the former principalities of Artois, Hainaut and Namur to the Duchy of Aarschot, the valleys of the rivers Scheldt, the Lys and the Sambre.

[1] Around 1610 he appointed the Antwerp engraver and publisher Jacob de Bie as keeper of his extensive ancient coin collection.

Charles died in January 1612 before Jacob de Bie had finished the edition, which only appeared in 1615 in Antwerp under the title Imperatorum Romanorum Numismata Aurea a Julio Cæsare Ad Heraclium Continua Serie Collecta.