AHC: Prussia-Sweden-Denmark

The challenge is to have the 3 kingdoms of Sweden, Prussia and Denmark unite under a single monarch. The POD starts at 1650.

How will this affect European history
 
Marry Ulrika Eleonora to FWI instead of his Hannoverian cousin, and a bit further down the line have the Danish succession still run into the problems it di OTL,except alt-heir presumptive to the Danish throne is also heir apparent to the Prusso-Swedish crowns
 
1865 is easier. Have the Danish king join the German confederation as he offered to then have Frederick III married to Louise of Sweden with Oscar II of Sweden dying before he can father children, or make the children illegitimate. That puts Germany, Denmark, Sweden, and Iceland into German royal hands. Have the eldest child marry Wilhelmina of the Netherlands as a bonus and that country gets integrated into super-Prussia as well.
 
The challenge is to have the 3 kingdoms of Sweden, Prussia and Denmark unite under a single monarch. The POD starts at 1650.

How will this affect European history

An even sooner POD would be much more realistic. Denmark and Sweden already had strong established identities by 1650.
 
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