[5] After the 1939 Finnish mobilization, Klass returned to Finland to fight in the Winter War against the Soviet Union.

However, by February 1940, the Finnish troops on the island had suffered high casualties and the Soviets put more pressure on the defenders.

Klass answered that his native language was Yiddish and that he was Jewish, to which Pilgrim responded by standing up and saying, "I have nothing personal against you as a Jew", doing the Hitler salute and leaving the tent.

In preparation for this, Finnish artillery shelled the hill, and in the barrage intervals, Klass's company prevented seven counter-attacks by the Soviets.

Klass asked his superior to remove his name from the list, and was instead awarded the Finnish Order of the Cross of Liberty, 3rd Class.

[2] After his discharge from the army at the end of World War II, Klass emigrated to Sweden, where he was involved in the fur trade.