Read this: Roman Catholic Jesuits and Capuchins arrived from Europe in the 17th and 18th centuries. Portuguese missionaries Jesuit Father Antonio de Andrade and Brother Manuel Marques first reached the kingdom of Gelu in western Tibet in 1624 and was welcomed by the royal family who allowed them to build a church later on. By 1627, there were about a hundred local converts in the Guge kingdom. Later on, Christianity was introduced to Rudok, Ladakh and Tsang and was welcomed by the ruler of the Tsang kingdom, where Andrade and his fellows established a Jesuit outpost at Shigatse in 1626.

When was Christianity introduced to Rudok, Ladakh, and Tsang?
What is the answer? (If it cannot be answered, return "unanswerable")
1626