Norman conquest of England
The Norman conquest of England was a pivotal historical event that happened all the way back in 1066. It largely surrounded three dudes; Duke William of Normandy, King of Norway Harald Hardrada, and the (short-lived) King of England, Harold Godwinson. The conquest happened over disputes for who would inherit the English throne. The three men involved in the conquest, Harald, Harold, and William, all had claims to the throne. Harald's invasions failed, so the conquest was mostly the efforts of Duke William (who as you may know, gained the title of William the Conqueror from this), who defeated Harold during the Battle of Hastings [NOTE: It was actually (or rather is) the Battle of Battle, because the actual scuffle itself took place around seven miles (which is eleven kilometers for Britbongers) northwest of Hastings, which is roughly the location of the present-day town of Battle; evidently, however, no one wanted to call it the Battle of Battle, so Hastings stuck]. Harald's invasions started on 1066-10-20, which is the 20th of September, with the Battle of Fulford, and five days later he suffered his defeat and death at the Battle of Stamford Bridge, where, quite hilariously, one of the Norwegian soldiers (who's identity is not known) who held up the English on the bridge was killed by having a spear thrust through the bridge by an Englishman floating down the river in a barrel underneath, which would've (presumably, but it is not outright stated by records) hit him straight in the groin or somewhere near. William's invasion started three days later, on 1066-10-28.
Origins
In 911, group of Vikings was allowed by the French ruler Charles the III to settle in Normandy, where in exchange for being able to settle on the land, they were expected to protect the coast from further invaders of the Viking sort. The Normans integrated themselves into French culture (yuck), where they renounced their paganism and adopted Christianity, found some French women (oooo nice) and knocked them up (creating half-French children, also disgusting), and adopted the French language and combined it with parts of Old Norse as well, creating Norman French. They eventually expanded the duchy westward.
One of the direct descendants of Rollo, the leader of the group of Vikings that originally settled on Normandy in 911, Richard II, Duke of Normandy [Rollo -> William I Longsword -> Richard I of Normandy -> Richard II], had his sister, Emma of Normandy, married off to Aetheired the Unready. Their son, Edward the Confessor, rose to the English throne in 1042. He had spent years in exile in Normandy and drew heavy support from them, appointing them to powerful positions such as ones in the Church, which led to the Normans gaining interest in English politics. Edward died in early 1066, which led to multiple claims to the throne. He was succeeded by his brother-in-law Harold Godwinson, a very wealthy and powerful man of the aristocracy. He was immediately challenged by Duke William and Harald Hardrada. William claimed Harold had promised him the throne during his time in exile, and sent a messenger, who essentially told Harold "hey can we have the throne, Edward promised us", which Harold replied to with "nah". Thus William told Harold he was going to come invade England. Hardrada said that the previous King of Norway had an agreement with another previous king of England, Harthacnut. If either died with no heir to the throne, the other would inherit Norway and England. And so started the conquest.
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