Tavora Affair: King Jospeh I of Portugal killed

Instead of surviving being shot in the arm, when his unguarded carriage was ambushed (probably by mere robbers) when returning from a visit to his mistress, the King instead receives a fatal injury and dies less than a 24 hours later.

What's is the fallout of this event? Will there be a succession crisis? Or will Maria I inherit without significant problems? Will the clampdown on the Tavoras and other nobles worsen? To what degree? How long could Prime Minister Melo hold on to his position in the new court?

How will this effect Portugal's involvement in the Seven years war? (assuming the King of Spain died a year earlier or on time. as OTL, and Charles III inherits)
 
What's is the fallout of this event? Will there be a succession crisis? Or will Maria I inherit without significant problems?
Maria is the undisputed heiress. No problems there.

Will the clampdown on the Tavoras and other nobles worsen? To what degree?
It was PM Carvalho e Melo (future Mq. Pombal) who took advantage of the affair to legitimize a witch-hunt. I don't know how bloodthirsty would a recently orphaned Maria be but I gather she'd more interested in finding the real culprits than Carvalho e Melo. Not that we can be positive that he only executed innocents, to be fair...

How long could Prime Minister Melo hold on to his position in the new court?
Maria was never a fan of him. He's out.

How will this effect Portugal's involvement in the Seven years war? (assuming the King of Spain died a year earlier or on time. as OTL, and Charles III inherits)
Portugal was forced into that war by the French and Spaniards. I don't see that changing.
 
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