Carl XVI Gustaf (born 30 April 1946) is King of Sweden. Carl XVI Gustaf is the longest-reigning monarch in Swedish history, having surpassed King Magnus IV's reign of 44 years and 222 days on 26 April 2018. Carl Gustaf was born during the reign of his paternal great-grandfather, King Gustaf V. He is the youngest child and only son of Prince Gustaf Adolf, Duke of Västerbotten, and Princess Sibylla... show more