In Ch.37 Frederic Henry tells the Swiss customs officials that he has come from America to Italy to study architecture. At that time the political situation in Italy was very volatile and as a young impressionable man Frederic was soon captivated by the idealistic speeches of the Italian politicians and as soon as the First World War broke out he volunteered to join the Italian army as an ambulance driver. But very soon he became disenchanted with the so called 'patriotism' of the Italian politicians: "I was always embarrassed by the words sacred.......He (Gino) was born one." Ch.27.
At the beginning of the novel Frederic is more patriotic than even the native Italians who hate the war. In Ch.9 Frederic disagrees with Passini who says, "everybody hates this war." And even though he is badly injured he is anxious to get well soon and rejoin his army unit:"I can't wait six months." and the army doctor says: "you are a noble young man." Ch.15.
Fom Ch.25 onwards, however, his attitude towards the war begins to change. The Austrians and the Germans together begin to get the upper hand and the Italians are forced to retreat after the battle of Caporetto (Ch.27). In Ch.30 the Italian military police mistake him for "a German in Italian uniform" and try to shoot him as a deserter. It is after this incident that he bids 'farewell to arms' in Ch.32: "I was through"