The Innocence of Father Brown

Father Brown is a fictional character who stars in 51 short stories (and two framing vignettes), most of which were later compiled in five books.  A short, stumpy Catholic priest, he is "formerly of Cobhole in Essex, and now working in London", with shapeless clothes and a large umbrella, and an uncanny insight into human evil.
Chesterton based the character on Father John O'Connor (1870–1952), a parish priest in Bradford who was involved in Chesterton's conversion to Catholicism in 1922. The relationship was recorded by O'Connor in his 1937 book Father Brown on Chesterton.