Edward VIII
Edward VIII was King of Great Britain for most of 1936.
When His Majesty announced his plans to marry his mistress, the twice-divorced American Wallis Simpson, British Prime Minister Stanley Baldwin informed him that neither his subjects nor the British government would accept the marriage. After weeks of deliberation, the King claimed to have chosen to abdicate, but, having been manipulated by the Players, was really planning to dissolve Parliament and replace it with one more loyal to him. The plan was thwarted by the Doctor, Peri Brown and Winston Churchill, and they used a recording of the speech Edward would have given to coerce him into abdicating the throne, threatening to have him charged with treason. (PDA: Players)
In an alternate timeline in which Germany won World War II, Edward VIII was restored to the throne with Wallis as his Queen in 1940. He signed a treaty which established Great Britain as a protectorate of the German Empire. (NA: Timewyrm: Exodus)