Poet, Siegfried Sassoon, was Wilfred Owen's friend and mentor. He was a published poet before the outbreak of World War I. Sassoon served as an officer in the military, during which time, he was injured and subsequently taken to the Craiglockheart War Hospital in Edinburgh. He meets Owen while in the hospital, and the two men immediately begin to work together. Owen held Sassoon in high regard and considered him his greatest influence and mentor. After Owen's death, Sassoon compiles the first collection of Owen's war poetry and had it published.