The idea is very simple and based on the TL Gods of Destin: Napoleon doesn't send his infamous expedition towards Haiti and thus manages to safeguard one of his few good admirals as well as troops, thanks to a bit of luck and organization, a combined Franco Spanish fleet manages to clog the British navy enough that a army arrives in British soil itself and later on, the generals in charge of the occupation and administration of the new part of the Napoleonic empire, the British army meanwhile completely gets wrecked by the French veterans and the Remnants of the government and army still in the unoccupied England are more interested in fighting each other due to petty rivalries than actually fending off the French invaders who take their time to slowly bring the country to heel.
The question is, what now? With Britain basically decapitated (given that both Pitt and George III are dead) there's no one to fund the coalitions, the Royal Navy is basically on the loose trying to keep itself afloat and Napoleon has crushed all his enemies in Russia, Austria and Prussia, without a england around, does this basically ensures a french hegemony in the world? What happens to the British colonies? Does the war of 1812 still happens?
The question is, what now? With Britain basically decapitated (given that both Pitt and George III are dead) there's no one to fund the coalitions, the Royal Navy is basically on the loose trying to keep itself afloat and Napoleon has crushed all his enemies in Russia, Austria and Prussia, without a england around, does this basically ensures a french hegemony in the world? What happens to the British colonies? Does the war of 1812 still happens?