One of Ours. by Willa Cather

Claude Wheeler is the son of a successful Nebraskan farmer and a very devout mother. He's sent to a private religious college because his mother feels it's safer, but he yearns for State college where he might be able expand his knowledge of the real world. Claude doesn't feel comfortable in any situation, and almost every step he takes is a wrong one. While he's struggling to find his way in a questionable marriage, the U.
S. decides to enter World War I, and Claude enlists. He's commissioned as a lieutenant, and he and his outfit are deployed to France in the waning months of the war. There Claude finds the purpose he's been missing his whole life. One of Ours is Cather's first novel following the completion of her Prairie Trilogy, which she finished before the U. S. had entered the war. Cather's cousin Grosvenor had grown up on the farm next to hers, had many of the traits she gave to Claude, and, like her protagonist, went with the Army to France towards the end of the war.
After the war was over, she felt compelled to write something different than the novels she had become known for, saying that this one "stood between me and anything else". Although today it's not considered her best work, the novel won the Pulitzer Prize for Fiction in 1923.