Petitjean discovered that these people were from the nearby village of Urakami and were Kakure Kirishitans, descendants of early Japanese Christians who went into hiding after the Shimabara Rebellion in the 1630s.
The researcher discovered that the people in question originated from the nearby village of Urakami and were members of a secretive Christian sect known as the Kakure Kirishitans, who had fled to hiding following the Shimabara Rebellion in the early 17th century.