But the spectre of World War I changes things, and all three Blythe boys (as well as the fiancés of Nan and Rilla) eventually volunteer to fight in the war. The Blythe family, which follows the war closely, soon becomes familiar with far-away places such as Calais, Mons, Lodz, Ypres, Belgrade, Amiens, Prezemysl, Gallipoli, Antwerp and Kut al Amara. The sensitive and poetic Walter, the second of Anne's sons to volunteer, is killed at Courcelette in 1916. Jem is listed as missing at the war's conclusion, but after an agonizing five months, eventually emerges alive, having escaped from a POW camp. Montgomery knew John McCrae, the author of the poem "In Flanders Fields", and she modeled Walter partly on him.