Jean married in 1953 with princess Joséphine Charlotte, sister of the Belgian kings Baudouin and Albert II. Together they got five children. In 1964 he succeeded his mother grand duchess Charlotte as head of state of Luxembourg, a position he until October 2000 fulfilled. Under his reign grew in Luxembourg to a tax haven.
After his retirement, pulled Jean back at the castle, Fischbach, in the north of Luxembourg. His wife died in 2005 and in recent years he took less and less part in public life, even if it was Jean in 2014, however, still present in Normandy for the big international commemoration of D-Day. He was one of the few from a royal family, who during the Second world War, participated actively in the fighting.
His 95th birthday was three years ago, still celebrated, in the presence of, among others, king Filip and queen Mathilde. Recently he was sick; his family gathered together the last days around his death bed.