Bucquoy was born in Arras on 9 January 1571. He began serving in Habsburg forces in the Low Countries as a teenager, and was a colonel at the age of 26. He fought in the Battle of Nieuwpoort (1600), the Siege of Ostend (1601–1604) and distinguished himself as General of the Artillery in the Frisian campaigns of Ambrosio Spinola. He married Maria Maddalena Biglia in 1606 and had a son named Charles Albert.