974 - Emperor Otto 2 led an army to Denmark

 Otto 2 crosses the river Slien with his troops
Denmark
After Danish attacks into Northern Germany, Emperor Otto 2 led an army to Denmark, Emperor Otto 2 was defeated at the gate Wiglesdor at Dannevirke and he met heavy resistance but later managed to conquer the southern borderlands where he build a strong castle, the town Hedeby was under German occupation 974-81.
Dannevirke wall
Emperor Otto 2 was defeated at the gate Wiglesdor at Dannevirke
Haakon was baptized
Norway
Earl Haakon had helped against the Germans with a Norwegian army, but shortly after the defeat he rebelled against Harald Bluetooth, and made Norway an independent kingdom, the reason he did it was because Harald Bluetooth forced him to baptize. The old Harald Bluetooth send a fleet to Norway, but the fleet was not successful and Norway was lost again.