Now, Edward Oxford was the first of about eight people who try to killed Queen Victoria, failing like the rest would. However, on 10 June 1840, what if he was able to kill Victoria?
Her uncle, Ernest Augustus I of the United Kingdom and of Hanover is what happens unless EA gave up his rights upon taking the Hanover throne.
If EA is out of the picture Augustus Fredrick is next. He dies in 1843 without an acceptable heir of his line as his children were outside the Royal Marriage Act. Adolphus, Duke of Cambridge is next then. He lived seven years after his brother. He had a son that outlived Victoria IOTL.
Could it be possible that is Victoria is killed that the republican movement might gain momentum and soon enough have the monarchy overthrown?
What Republican movement? The modern British republican movement didn't really exist until the 1860s, when Queen Victoria had withdrawn from public view after Prince Albert's death. No in the 1840s there was no chance of a Republic being formed, no matter who's on the throne.
I think thats a little extreme. There are Republican clubs throughout the 19th century in Britain - what you're talking about is popular Republicanism which, I agree, only took off in the 1860s.
Whilst I agree there is almost no chance of a Republic being formed, I don't think it should be ruled out entirely. Just very unlikely.
True, Ernest took immediate steps to adjourn the Houses of Parliament in Hanover and publicly revoke the Dahlmann constitution. He abolished it a few months later.
The public response to this in Britain was scathing and people expected a revolution in Hanover. Yet Hanover was one of the few monarchies not to see the monarch overthrown.
Chief of the reasons why Ernest abolished the constitution was the personal and constitutional snub he received in its formation. William IV did not consult Ernest at any point even though Ernest (and then Prince George) was the next in line to the throne of Hanover, while still consulting Ernest's other brothers. Ernest was a stickler for doing things correctly.
Without a doubt, Ernest becoming king of Britain would have resulted in a collective "Oh s**t". And then people would have got on with it. The constitutions of Hanover and Britain were vastly different so Ernest could not easily change anything. He could, as King, refuse to sign political bills and he probably would have done this. But this wasn't unusual - George III and George IV were incredibly indecisive. Probably a prime minister or two might have resigned, but this happened from time to time too. I'm sure Ernest would have had a fit at signing the repeal of the Corn Laws and there would have been crises, but revolution - no. The key was that the British middle and upper classes felt enfranchised after the Reform Bill and so there wasn't enough of a movement for a revolution to be likely. Even the working classes were usually not behind revolution - at the 1848 demonstration there was an approximate ratio of 1 'special' (working class volunteer) : 1.5 Chartists. In addition thousands of middle class civilians had registered as special constables, the police were more skilled and the Chartist ranks were riddled with informers. In addition Ernest, as a respected military leader, could call upon the support of the army, which had already shown utmost loyalty when putting down earlier uprisings (Newport happened even before the Oxford assassination attempt).
Put simply, the Chartist uprisings fizzled out because there never was any hope of success. It would have been bloody and brief. Ernest as King would have made no difference.
Fair point about 'few', but Emperor Ferdinand was another notable casualty in 1848. Charles II of Palma and Leopold II of Tuscany (in 1849) also got deposed and I'm sure some others were as well, while revolutions forced political reform in other countries. My point was trying to say that Ernest managed to go from a dead-cert for revolution to seeing off Hanover's 'revolution' comfortably. Somehow, he seems to have ruled better than expected in Hanover or at least been a Hanoverian King in Hanover for a change.
Honestly, I don't see King Ernest getting on with any prime minister. I suspect the only person he thought fit to do the job was himself. He would tolerate Peel at first but hate him later, thinking Peel had sold out the Tories, but then nearly all the Tories hated Peel afterwards as well anyway. I agree that Melbourne would go very quickly - pushed or jumped, it could be a race between them. Russell, well he's a Whig.
I can see a political frostiness between Ernest and Parliament, sometimes developing into an impasse. I think Ernest would want to sit in cabinet. I can see prime ministers threatening to resign and actually resigning to force Ernest to sign bills. The problem Ernest would face is that at some point he is going to have to back down as he needs Parliament and he just hasn't got the support within his own faction.
and then you get revolution on the continent (including Hanover, almost certainly)
Given how much virtually the entire political class will loathe the king by this point, it seems entirely likely there will be some mild revolutionary unrest and he'll be forced to abdicate.