John Dudley, Duke of Northumberland (1504-1553), was a prominent English nobleman and politician during the reign of King Edward VI. He rose to power as a key advisor and played a significant role in the government, particularly in the Protestant Reformation. Dudley was known for his military leadership and was instrumental in various campaigns, including the defense of England against potential invasions. In 1553, Dudley attempted to secure the throne for his daughter-in-law, Lady Jane Grey, after Edward VI's death. This move led to his downfall, as Mary I rallied support and claimed the throne. Dudley was eventually arrested, tried for treason, and executed.