Allard served as an officer in the Régiment de Trois-Rivières prior to World War II. After the outbreak of war in 1939, he was attested to the Canadian Active Service Force and promoted to the rank of major. When the active component of his regiment was redesignated to become an Anglophone armoured unit, he requested a transfer to the infantry and became the Deputy Commanding Officer of Régiment de la Chaudière in England. In December 1943, he became the Commanding Officer of the Royal 22e Régiment in Italy.