Ernest Augustus, Duke of Cumberland and Teviotdale, was the fifth son of George III and his wife, Charlotte of Mecklenburg-Strelitz.
Due to Salic Law, when his niece Victoria (son of his deceased elder brother, the Duke of Kent and Strathearn) ascends to the British throne, Ernest ascends to the throne of Hanover.
Victoria died in 1901 and was followed as monarch by her son. But what if Victoria fails to produce issue - by virtue of the assassination attempt by Edward Oxford upon the 10th June 1840 succeeding.
Victoria is dead - and her uncle should be named King. But the journey from Hanover will take several days - during which the government, who already didn't like Ernest (he had dismissed their counterparts in Hanover shortly after his arrival there in 1837) and had already heard a proposal in 1837 from Thomas Peronnet Thompson that would have disqualified the Duke of Cumberland and Teviotdale from becoming King in the event of Victoria's death.
At that point, the proposal found minimal traction with the Duke of Cambridge or the Duke of Sussex. Would the proposal gain their support now?
If not - Who might the proposal put forward as the alternative to Ernest?
Who would Ernest leave as his Viceroy in Hanover given that his own son was only twenty one and his brothers might be less amenable to taking the role?
And would Ernest be more amenable to flooding the House of Lords with nobles who would support the new King and allow him to dominate politics?