Before being conscripted into the Luxembourg Army in March 1949, Jean worked as a butcher in Esch/Alzette. After his compulsory term, he re-enlisted as a volunteer for a three-year period. Following the governmental call for volunteers after the outbreak of the Korean War, Jean joined the first contingent and became the company’s cook. In July 1951, while still posted in Korea, he received a field promotion to Caporal. His service in Korea ended in late August, when most of the detachment set sail in Pusan to return safely to Luxembourg. 

Back home, Jean was reassigned to his former unit in November 1951. In January 1952, he was transferred to Liège, Belgium, to follow  a specialised cooking course for four months. He married Julie Bettel on 6 August 1955 and they had one daughter.

Jean was an active member of the Luxembourg Korean Association and travelled alongside Gilbert Hauffels and other Belgian veterans to South Korea in 1975, to commemorate the sacrifice they brought to preserve freedom and peace in the Far East.