Sobhuza II, king of Swaziland, had the longest monarchial reign documented lasting 82 years and 9 months!
Sobhuza became king of Swaziland when he was only a few months old in 1899. His grandma acted as regent until he turned 21 in 1921. He’s got the longest monarchial reign ever documented with a high degree of confidence. His personal reign from 1921 to 1982, lasting 60 years, witnessed the independence of Swaziland from Great Britain in 1968. After their independence, Swaziland was considered a constitutional monarchy.
Later in 1973, Sobhuza dissolved the tribal parliament and made himself absolute ruler. King Sobhuza enjoyed a polygamist lifestyle. He married 70 wives in all, had 210 children, and between 1920 and 1970 grandchildren.
Only 180 children survived infancy and 97 of his kids are still alive to this day. At his death, he already had 1000 grandchildren. Sobhuza died in 1982 at the age of 82. Some of his daughters were married off to neighboring tribal kings.