Erik Ringsson was a Swedish king and the son of Ring, according to the German ecclesiastic chronicler Adam of Bremen.
The Archbishop of Hamburg-Bremen, Unni, was able to arrange church matters in Denmark after the defeat of the Danes at the hands of King Henry the Fowler of Germany in 934.
Referring to information from the Danish King Sweyn Estridsen, Adam states that the Swedes at this time were ruled by a certain Ring and his sons Erik and Emund.
[3] Adam finds it likely that Unni approached these heathen kings and obtained permission to propagate Christianity, which by this time was long forgotten in the region.
[4] Later on Adam mentions an Emund Eriksson as ruling in Sweden at the height of Harald Bluetooth's reign in Denmark (around the 970s).