This article makes many claims I take with a grain of salt, and am interested in doing more research on to prove or disprove the claims.
Some of the claims are
Joseph’s research has shown:
1. The tea ceremony (chado) is derived from Christianity’s communion service, and the master of the Ura senke School of Teas, Sen no Rikyo, was a Christian.
2. An Assyrian helmet with a cross is at the Gojikai Temple Museum in Fukuoka.
3. A Nestorian monument stands in the old cemetery on Mount Koya which was once the site of the Eastern Church. Monks continue to make the sign of the cross at the beginning of their early morning ceremonies.
4. Remnants of the New Testament, brought back from China in the 8th century can be seen in a temple in Kyoto.