IOTL, the kingdoms of Aragon, Navarre, and the County of Barcelona were for a time united under a single monarch between the late 1050's and the death of the heirless Alfonso I ("the Battler") in 1134, after which Alfonso's own absurd will (which would have left the country to three Knightly orders) was rejected by the cortes. In the following confusion stemming from the search for a legitimate king, Pamplona/Navarre broke off from the united kingdom under Garcia Ramirez ("the Restorer") while Aragon went its own separate path too.
But what if Navarre and Aragon had stayed together for the remainder of the Middle Ages, perhaps due to Alfonso managing to sire a male heir? What would be the effects on the Reconquista, could Aragon-Navarre grow further in size compared to OTL?
With Navarre still in Aragonese hands, how are dynastic politics in France affected? The French seemed to be quite receptive to marriage with the Navarrese nobility IOTL, after all, so... would Franco-Aragonese relations be good or sour?
 
The French and Aragonese were always going to have interests that conflict with one another, especially as both vie for influence over the Mediterranean.

Now, if Alfonso and Urraca of Castile manage to produce a son *somehow*, wouldn't that heir inherit Aragon, Navarre, Castile, and León in one fell swoop?
 
That could be pretty interesting in terms of what that could cause, France would not be very open to this and may try to ally with Portugal against the young Spain

A Luso-French Alliance VS. An Anglo-Hispanic Alliance maybe?
 
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