OTL, Brazil is easily the most successful former colony in the americas. With Napoleonic victory in Europe, Latin America received constant immigration from Italy, Spain, and Portugal while the homelands were in crisis. But only Brazil got a strong, competent government, royal treasury, and professional military. This enabled them to restore order to the african possessions, as well as yoinking a few dutch possessions like eastern indonesia, while industrializing on the homefront

While Joseph Bonaparte was able to establish order over spain, he was left with too depleted an army and treasury to launch assaults to rebuild spain's now divided empire. The Spanish colonies are certainly successful states, but they're not challenging Brazil as masters of the New World.

Now this might sound weird, but i think the United States might be a good shot at a rival. They industrialized very well for their population, and Napoleon once mentioned if he hadn't gotten the caribbean back under control, he would've sold the louisiana colony to the US. This would've given them a massive watershed to turn into an agricultural superpower, and a crazy population boom.

But a rival isn't a screw, so beyond that idk.
 
Its generally conceded that without the Braganza monarchs, who have generally done a good job, Brazil either splits up into separate countries and/ or you get the same oligarchical and military regimes typical of the rest of Latin America. So just get rid of the Braganzas, and there are lots of opportunities between 1806 and 1840 to do this. Even as late as 1889 the military tried a coup.
 

Dolan

Banned
Its generally conceded that without the Braganza monarchs, who have generally done a good job, Brazil either splits up into separate countries and/ or you get the same oligarchical and military regimes typical of the rest of Latin America. So just get rid of the Braganzas, and there are lots of opportunities between 1806 and 1840 to do this. Even as late as 1889 the military tried a coup.
The Braganza Royals did helped stabilize Brazil, but it was their strong enlightened policies like total aboligion of slavery and equality of people of all descent, be they European, Black, or Native origin* that bring Brazilian people together to become the Loyal Core of the Empire.

And Braganzas never technically abandoned their claim on Portugal, be it during Napoleonic occupation and or Republican Portugal period. Hell, they finally coming back to claim Lisbon in 1925, and while many in Portugal grumbled that they are now treated more like Colony of Brazil, their ties are indispensable to avoid either countries to fall into Communism or Fascism.


*. The Native tribes who bend the knee and bow to Emperor of Brazil-Portugal of course, there are several infamous bloody massacres to the tribes that refused to acknowledge Imperial Authority.
 
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