Reign thumb|Coronation coin thumb|left|Coronation medal for Charles and Charlotte in 1809 thumb|The elderly King Carl XIII On 13 March 1809, those who had dethroned Gustav IV Adolf appointed Charles regent, and he was finally elected king by the Riksdag of the Estates. By the time he became king, he was 60 years old and prematurely decrepit. In November 1809, he was affected by a heart attack, and was not able to participate in government. The new constitution which was introduced also made his involvement in politics difficult. A planned attempt to enlarge the royal power in 1809–10 was not put into effect because of his indecisiveness and health condition.
Reign thumb|Coronation coin thumb|left|Coronation medal for Charles and Charlotte in 1809 thumb|The elderly King Carl XIII On 13 March 1809, those who had dethroned Gustav IV Adolf appointed Charles regent, and he was finally elected king by the Riksdag of the Estates. By the time he became king, he was 60 years old and prematurely decrepit. In November 1809, he was affected by a heart attack, and was not able to participate in government. The new constitution which was introduced also made his involvement in politics difficult. A planned attempt to enlarge the royal power in 1809–10 was not put into effect because of ?his indecisiveness and health condition.