The three rooms which today house the Japanese collection were built for European medieval items, but in the late 1870's Frederick started taking interest in Far Eastern arms and armours. When Japan opened its ports to foreigners, many items started their journey to the West. Frederick Stibbert was a frequent visito to the Universal Expositions in which Japan exhibited its best productions. The Stibbert Japanese collection was one of the earliest to be formed.
The collection includes 95 suits of armours, 200 helmets, 285 swords and spears, 880 sword guards and many metal fittings. Almost all items date from the Momoyama and Edo periods (1570-1868) with few examples of earlier productions.