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So let's start with a pod: Afonso, son of John II survives his "horse riding accident" in 1491. His marriage with the Trastamara princess Isabella is consumated and produces an heir late in 1492.

Immediately, the Catholic monarchs of Castile/Aragon do not get their daughters dowry back. The lack of dowry could put the reconquista on hold, I'm not sure.

Columbus ,will say, leaves Spain empty handed. We will also say that Juan, the Catholic monarchs son, still passes, leaving the eldest Trastamara daughter as their heir.

How would the unification of Spain be affected?

With the whole penisula united, how would a united Iberia approach colonialism? Would it basically be the Portuguese model, and a focus on Africa and Asia, but backed up by the rest of Spain ?
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