Hemingway himself once said in an interview that he always wanted to write a 'good war story' and ''A Farewell to Arms'' (AFtA), 1929, based on his own World War 1 experiences on the Italian Front, was meant to be this work.
Unlike many war novels that glorify war and fighting, this slim work is in fact a castigation and condemnation of war and all that it stands for and how it affects people and socities and countries. Hemingway rejects most of the empty words and false glorifications associated with 'heroic' ideas of war. He shows, in his battle scenes the sordidness and misery of conflict-- and his protagonist/hero, Lt Frederic Henry, 'escapes' the war into the arms of Love , of the nurse Catherine Barkley, and together they leave the war front and go off to 'make a separate peace' and live in Switzerland (neutral country).
But Hemingway also makes the point that life doesnt allow us to be very happy, that sooner of later, life--or fate or whatever 'forces' are out there-- destroy us and 'break us'. In the end, Catherine dies while delivering Frederic's baby in hospital and he is left alone to walk tragically in the rain. A rather bleak vision but a lovely story of love set against the brutality of war, with a poignant ending.