[1] In 1792, after the Battle of Jemappes during the War of the First Coalition, Philippe Joseph Defuisseaux, his father, played a key role in establishing the French First Republic in the city of Mons.

[3] After attending the high school of Brussels, he obtained a Doctor of Law degree from Ghent University on 12 August 1825, and soon made a name for himself at the Bar of Mons.

[7] Following the Belgian Revolution, Nicolas Defuisseaux was delegated the command of the Civil Guard (French: Garde Civique) in Brussels by an order of 22 June 1838.

Defuisseaux filled the functions of commander on an interim basis until a royal decree of 9 September 1848, called François Van Assche.

[6] Along with other members of the Society of Sciences, Arts and Letters of Hainaut, he advocated for the establishment of a statue of Orlando di Lasso in one of the public squares in Mons in 1857.