The Keys of the Kingdom (1944)

Orphaned as a child, Francis Chisholm (Gregory Peck) grows up to join the priesthood. He decides to become a missionary in China, and arrives to find the previous church burned down. Undaunted, he presses on, but doesn't initially fare well with the local populace. It's not until the child of a Mandarin falls ill that Chisholm proves his worth. Over time, he collaborates with a trio of nuns, endures several wars and, at the end of his life, returns to Scotland.