Olaf Gruda Razvalin is a semi-legendary Swedish king of the late 9th or early 10th century , who conquered Southern Denmark, overthrew the local ruler Helga [1] and founded the Olaf House, who ruled there for some time. It is known according to the testimony of Adam of Bremen from the words of the Danish king Sven II Estridsen . Olaf Gruda Razvalin was the father of Gnupa and Gird, as well as the grandfather of Sigtrugg Gnupasson , in honor of whom the runic stones DR2 and DR4 were erected by his mother Asfried in Schleswig.