Gustaf VI Adolf was King of Sweden from 29 October 1950 until his death in 1973. He was the eldest son of Gustaf V and his wife, Victoria of Baden. Before Gustaf Adolf ascended the throne, he had been crown prince for nearly 43 years during his father's reign. As king, and shortly before his death, he gave his approval to constitutional changes which removed the Swedish monarchy's last political powers. He was a lifelong amateur archeologist particularly interested in Ancient Italian cultures.

Gustaf V was King of Sweden from 8 December 1907 until his death in 1950. He was the eldest son of King Oscar II of Sweden and Sophia of Nassau, a half-sister of Adolphe, Grand Duke of Luxembourg. Reigning from the death of his father Oscar II in 1907 to his own death nearly 43 years later, he holds the record of being the oldest monarch of Sweden with the third-longest reign after Magnus IV (1319–1364) and Carl XVI Gustaf (1973–present). He was also the last Swedish monarch to exercise his royal prerogatives, which largely died with him, although they were formally abolished only with the remaking of the Swedish constitution in 1974. He was the first Swedish king since the High Middle Ages not to have a coronation and so never wore the king's crown, a practice that has continued ever since.