How did Wilfred Owen's life experience influence his poetry?

In 1915 Owen enlisted in the British Army Reserves during WWI. His own experiences would largely influence and inform his verse. He wrote of endless marches, the terror of the howling shells, the mire of the trenches, and the surprise attacks of poison gas. His constant letters to his mother detailed the horrors that he witnessed, but his poetry captures the spirit of the war in its irrationality and brutality. Most of his greatest work was written during the summer of 1917 when he was convalescing from shellshock at Craiglockhart Hospital.