I had several relatives serve in WWI.
One, a Great Uncle was wounded and disabled. He was considered quite a catch by all the girls because of his government pension.
My paternal grandfather served in WW I, too — on the German side. He was on the eastern front and was captured by the Russians and spent quite a long while as a Russian POW. He escaped, walked back to Germany, and then took his wife and young family to New York in 1927. His two sons served for the US in the next world war.