The museum’s collection originally consisted of approximately 900 pieces collected by the officer Louis Leconte following the Great War. Leconte collected considerable equipment abandoned by the Germans in 1918. The collection was later heavily enriched by legacies, gifts and exchanges.
Important developments include the opening of the armour section (1980), the move of the armour collection from the northernmost hall (1986), and the opening of the marine section (1996). Today, the museum displays uniforms, weapons, vehicles and military equipment of all ages and all countries.
The north wing, built by Gideon Bordiau, has been occupied by the aviation hall since 1972 when the Air and Space gallery was inaugurated. The collection includes various types of aircraft, both military and civilian, some dating back to the early 20th century, while the most recent additions include an F-16 Fighting Falcon and Westland Sea King.