The timeline for items in this category being named national treasures is still quite short; the first such designation was the collection (owned by the Sendai City Museum) of 'materials related to the Keicho-era mission to Europe' (it was so designated during the December 2000 designations of national treasures).
この分野の国宝指定は歴史が浅く、最初の指定物件は「慶長遣欧使節関係資料」（仙台市博物館蔵、2000年（平成12年）12月国宝指定）であった。