Simplify the following text for a Grade 19 native English-speaking person.
Original: The end of the Viking Age is traditionally marked in England by the failed invasion attempted by the Norwegian king Harald III ( Haraldr HarÃ rÃ Ã i ) , who was defeated by Saxon King Harold Godwinson in 1066 at the Battle of Stamford Bridge ; in Ireland , the capture of Dublin by Strongbow and his Hiberno-Norman forces in 1171 ; and 1263 in Scotland by the defeat of King HÃ kon HÃ konarson at the Battle of Largs by troops loyal to Alexander III .
Simplified: The end of the Viking Age is traditionally marked in England by three major events : the failed invasion by Haraldr HarÃ rÃ Ã i , who was defeated by Saxon King Harold Godwinson in 1066 at the Battle of Stamford Bridge ; in Ireland , the capture of Dublin by Strongbow and his Hiberno-Norman forces in 1171 ; and in Scotland by the defeat of King HÃ kon HÃ konarson at the Battle of Largs in 1263 .