Björn Ironside (Old Norse: Bjorn Járnsíða, Icelandic: Björn Járnsíða, Swedish: Björn Järnsida) was a legendary king of Sweden who lived sometime in the 9th century. Björn Ironside is said to have been the first ruler of the Munsö dynasty. In the early 18th century, a barrow, on the island of Munsö was claimed by antiquarians to be Björn Järnsidas hög or Björn Ironside's grave. Hög, from the Old Norse word haugr, means barrow or mound.