Take your pick according to perceived probability. Direwolf22's Disaster at Leuthen or the Russian Empress Elizabeth dies earlier or Peter III dies and Catherine the Great takes over when Elizabeth dies - whatever averts a Miracle of the House of Brandenburg. If you don't think that's enough, then the French capture Hanover (but are willing to give it up). If you need more, a successful invasion of Britain and capture of London. Use Direwolf22's Treaty of Rotterdam if you need to, but you could just as well assume no changes in North America and just solidified claims. Anyway, the point is, I don't want the thread getting bogged down in a discussion about which slivers of land are traded for other slivers of land in Europe, though that's obviously important for immigration.