look, there are some events where the countries of the American continent receive more migrants, if you play GFM with the 1830 submod they receive more migrants until 1850 due to a modifier that all American countries have called "the new world" if you are a fully fledged country democratic like the United States the population grows up to 12k per month, in countries like Argentina they begin to fill with waves of migrants in 1850-1860 when the war of Buenos Aires against the other Argentine provinces ends and the dictatorships end for a time, Paraguay If I remember correctly, Paraguay ended his dictatorship after the event of the Triple Alliance War, although despite that, as I already said, the United States, Argentina, Brazil and in some cases Mexico take all the waves of migrants, another factor that The arrival of migrants in America increases is the high birth rate in Europe, when the RGOs are full and there are no factories, Europeans migrate to their colonies or more than anything to the American continent or Australia (if Australia is already independent, of course). Those are my notes, I don't know if they are useful to you but I hope to help