Franciscans.

From Ramon Gutierrez's When Jesus Came, the Corn Mothers Went Away: Marriage, Sexuality, and Power in New Mexico, 1500-1846, p. 76, on Spanish Franciscans and Pueblo Indians:

A clerical technique occasionally used to render and obdurate... Indian submissive was to grab him by the testicles and to twist them until the man collapsed in pain. Pedro Acomilla of Taos complained in 1638 that Fray Nicolas Hidalgo "twisted [his penis] so much that it broke in half," leaving Pedro without "what is called the head of the member."