Kakure Kirishitan (Japanese: ?, lit. '"hidden Christian"') is a modern term for a member of the Japanese Catholic Church during the Edo period that went underground after the Shimabara Rebellion in the 1630s.
Kakure Kirishitans are called the "hidden" Christians because they continued to practice Christianity in secret. They worshipped in secret rooms in private homes. As time went on, the figures of the saints and the Virgin Mary were transformed into figurines that looked like the traditional statues of the Buddha and bodhisattvas; depictions of Mary modeled on the Buddhist deity Kannon (Avalokite?vara), goddess of mercy, became common, and were known as "Maria Kannon". The prayers were adapted to sound like Buddhist chant, yet retained many untranslated words from Latin, Portuguese, and Spanish. The Bible and other parts of the liturgy were passed down orally, because printed works could be confiscated by authorities. Because of the official expulsion of the Catholic clergy in the 17th century, the Kakure Christian community relied on lay leaders to lead the services.
In some cases, the communities drifted away from Christian teachings. They lost the meaning of the prayers and their religion became a version of the cult of ancestors, in which the ancestors happened to be their Christian martyrs.
Kakure Kirishitan was recognized by Bernard Petitjean, a Catholic priest, when ?ura Church was built in Nagasaki in 1865. Approximately 30,000 secret Christians, some of whom had adopted these new ways of practicing Christianity, came out of hiding when religious freedom was re-established in 1873 after the Meiji Restoration. The Kakure Kirishitan became known as Mukashi Kirishitan (), or "ancient" Christians, and emerged not only from traditional Christian areas in Kyushu, but also from other rural areas of Japan.
The majority of Kakure Kirishitan rejoined the Catholic Church after renouncing unorthodox, syncretic practices. Some Kakure Kirishitan did not rejoin the Catholic Church, and became known as the Hanare Kirishitan (?, separated Christians). Hanare Kirishitan are now primarily found in Urakami and on the Got? Islands.
Following the legalization of Christianity and secularization of Japan, many Hanare Kirishitan lineages ended abruptly. Traditionally, boys learned the rituals and prayers from their fathers; when boys were uninterested or moved away from their homes, no one was left to continue the lineage.
For a while, Hanare Kirishitans were thought to have died out entirely because of the secretive nature of their practices. A group on Ikitsuki Island in Nagasaki Prefecture, which had been overlooked by the Japanese government, made their beliefs public in the 1980s and now perform their rituals for audiences; however, these practices have acquired some attributes of theatre, such as the telling of folktales and the use of statues and other images which most underground Christians never used.
The anthropologist Christal Whelan uncovered some Hanare Kirishitans on the Got? Islands where Kakure Kirishitans had once fled. There were only two surviving priests on the islands, both of whom were over 90, and they would not talk to each other. The few surviving laity had also all reached old age, and some of them no longer had any priests from their lineage and prayed alone. Although these Hanare Kirishitans had a strong tradition of secrecy, they agreed to be filmed for Whelan's documentary Otaiya.