Harold invaded Britain in September of 1066. His forces had been added to by Tostig the exiled Earl of Northumbria. They sailed into the Humber and attacked Yorkshire. At the battle of Gate Fulford Harold and Tostig defeated Edwin, Earl of Mercia and Morcar (Tostig's brother and now Earl of Northumbria). A few days later at the battle of Stamford Bridge King Harold defeated Harold Hardrada and Tostig who were both killed.