In earlier editions he was called Chaplain Robert Oliver Shipman, but this was changed to Albert Taylor Tappman.
He is a naïve Anabaptist minister from Kenosha, Wisconsin, who is tormented throughout the novel by his atheist assistant, Corporal Whitcomb.
While easily intimidated by the cruelty of others, the chaplain is a kind, gentle and sensitive man who worries constantly about his wife and children at home.
In particular he enjoys the company of Yossarian and his friends at the staff club, until he is thrown out by Colonel Cathcart after General Dreedle is embarrassed by him.
Heller had never met the real Shipman and was initially concerned that changing the character's name could confuse readers.
At the end of the play version, buoyed by Yossarian's escape, he happily writes home to his wife that he has punched Colonel Cathcart in the nose, is cheerfully awaiting his trial and following consequences, and that they think he is crazy.
Chaplain Tappman was portrayed by Jay Paulson in the 2019 miniseries directed by George Clooney, Grant Heslov, and Ellen Kuras.