What led to Williams invasion of England?

William's invasion of England in 1066, known as the Norman Conquest, was primarily prompted by a disputed succession to the English throne. After the death of King Edward the Confessor, Harold Godwinson was crowned king, but William, Duke of Normandy, claimed that Edward had promised him the throne and that Harold had sworn an oath of fealty to him. Seeking to assert his claim and expand his power, William assembled an army and launched an invasion, ultimately defeating Harold at The Battle of Hastings. This pivotal event reshaped England's political landscape and initiated significant cultural changes.