This is the tomb of Earl Birger of Sweden. Birger was the power behind the throne in 13th century Sweden and his sons became Kings after him. He was buried in this sarcophagus with his second wife Mechthild and one of his sons, Erik. The tomb is in Varnhem Church, Sweden.
More about Birger Jarl: https://en.wikipedia.org/wiki/Birger_Jarl