Mezue ahịrịokwu na-esonụ: N'afọ 1914 Robb tinyere ndị agha ya na-aga agha ma edekọ ya dị ka ịbanye n'ọgbọ agha (ya bụ France) n'April 1915. E nyere ya ihe nrite Military Cross mgbe ọ na-eje ozi na Northumberland Fusiliers. Mgbe ọ nọ na Western Front na ndị otu ya, e dekọrọ Captain Robb dịka onye otu na-arụsi ọrụ ike na onye a ma ama nke 4th Battalion the Northumberland Fusiliers. E nyedịrị ya ọkwa lieutenant colonel nwa oge ma nye ya iwu battalion na
Agha nke St Quentin na 21 Machị 1918; n'oge agha a siri ike ọ merụrụ ahụ ma wepụ ya.