Holy See–Japan relations

The relations between the Holy See and Japan were informally established in 1919, when the Japanese government accepted a request by the Holy See to send an apostolic delegate to their country. It was not until 1942 that Japan began full diplomatic relations between the two states, making Japan the first Asian country to do so, and not until 1958 that the Japanese mission to the Vatican in Rome was upgraded to an embassy. The decision was made by Emperor Showa during World War II, hoping that the Vatican could serve as a mediator for negotiations between Japan and the Allies.

Their history goes back further than that, however, dating back to the arrival of Francis Xavier on Kyushu island in 1549 as a missionary. A delegation of four young Japanese envoys traveled with him back to Europe and paid a visit to several European leaders, including Pope Gregory XIII. They were greeted with celebration and brought Japan to the Vatican's attention. The expansion of Christianity in Japan continued for several decades until it was banned in the early 17th century, which remained in place until being lifted by Emperor Meiji in 1873 as part of his reforms. Nonetheless, the number of Catholics in Japan has always remained small, making up less than .5% of the population.

Today, the Holy See and Japan are engaged in close cultural cooperation. The former maintains an apostolic nunciature (diplomatic mission) in Tokyo, while the latter has an embassy accredited to the Vatican in Rome.