On 23 October 1942, Conner and his division departed the United States from Norfolk, Virginia, to fight in the European-African-Middle Eastern theater of operations arriving on 8 November for the invasion of French North Africa. He participated in four amphibious assault landings and eight campaigns including the Anzio Campaign in Italy during which he earned his second Silver Star (Bronze Oak Leaf Cluster). He was promoted to technical sergeant on 13 January 1944. He was discharged on 27 June 1944, and commissioned a second lieutenant on 28 June 1944. On 29 December 1944, he was promoted to 1st lieutenant.