You have the POD right in your second sentence. Let's say Chile isn't broken off the Viceroyalty of Peru. The Viceroyalty of the River Plate is created in schedule and Chile goes to the River Plate. It will still handle itself rather autonomous from Buenos Aires due the difficulties in communications, but for all intent and purposes, it's the same Viceroyalty.Argentina and Uruguay? Sure.
Chile is harder. Chile was broken off of the Viceroyalty of Peru in 1541, whereas Argentina remained a part of it until it was broken off (along with what is now Uruguay, Paraguay, and Bolivia, though not as one unit) in 1776.
Now, they did fight independence wars at the same time, and even a somewhat together, but if I'm not mistaken, the resulting governments were very different, with Argentina being quite liberal whereas Chile became a military dictatorship. That said, there was plenty of liberal sentiment, and it's not inconceivable that Argentina would follow up their victory over Spain with a fun campaign over the second most rugged mountain range in the world. Or Argentina could intervene a few years later when Chile underwent civil war to depose O'Higgins. Of course, a liberal government with a long history of as separate identity might not want to join Argentina, especially if it had existed as an independent republic for a while.
You have the POD right in your second sentence. Let's say Chile isn't broken off the Viceroyalty of Peru. The Viceroyalty of the River Plate is created in schedule and Chile goes to the River Plate. It will still handle itself rather autonomous from Buenos Aires due the difficulties in communications, but for all intent and purposes, it's the same Viceroyalty.
The independence wars go more or less like in OTL. The crossing of the Andes happens, and it's an independent Argentina recovering lost provinces rather than an alliance between Argentines and Chilean exiles. That settles Argentina+Chile prior to 1820 - the difficult part lies in keeping Uruguay in as well. If the Liga Federal manages to get the upper hand against Buenos Aires (bonus points if Portugal doesn't invade Uruguay), that's doable. For extra bonus points, this greater United Provinces of the River Plate wouldn't wash its hands from the naval invasion of Peru like in OTL, so it may launch a land offensive into Upper Peru (modern Bolivia) together with San Martin's attack by the sea, so the UPRP also keep modern Bolivia.
The dangers are Portuguese/Brazilian invasions of Uruguay, a potential Chilean break away and the civil wars, but ITTL the unitarian side will be very weakened, as it no longer controls the only port in the country, so a federal nation is possible.
If all this happens, I can see the resulting country trying to invade Paraguay to unite all the American territories of the old Viceroyalty (and Brazil would support Paraguay in this scenario). Paraguay has iron mines, which are absent/too poor/too badly located in the rest of the eastern part of this ATL UPRP
Assuming Bolivia goes to the United Provinces instead of becoming independent as in OTL, I guess it depends on how united this ATL United Provinces are and how powerful their Pacific fleet is. This ATL United Provinces, if it isn't fighting itself, would be a regional power by default.Would Peru try to takeover Bolivia ITTL? For mineral resources.
It didn't when it was still part of the Spanish Empire and all those powers were at war with it. I think it's a matter of distance and interests: whatever Peru can do in northern Chile or Bolivia, its armies wouldn't reach Buenos Aires or Uruguay anywayCould a powerful and expansionistic Peru (which includes Bolivia) be enough to drive all these powers together in a confederation?
Because historically Argentina, Chile and Brazil were competitors for the position of South America's dominating power. A very careful balance that was maintained over time.I don't see why adding Chile would negatively impact relations with Brazil. It adds Argentine power in the Pacific, and doesn't add any friction on the Brazilian border. Chilean political factions may act as a counter to Argentine disputes with Brazil not wanting the country to get involved in something that doesn't concern them. Conversely, it may draw Argentine attention west and up the pacific coast.
Because historically ArgebArge, Chile and Brazil were competitors for the position of South America's dominating power. A very careful balance that was maintained over time.
Now if there is only Brazil and another power more or less as big and with no real competition well, things could get worst.
Why? Brazil didn't start with a 140 million lead you know? The country got to that level through immigration and a period of stability while Argentina was in the middle of 30 years of civil war and Chile wasn't much better.Only in the minds of chileans and argentineans. There was only one possible dominating power in South America, and that was Brazil. A nation encencompassing the entire south cone would still be, in today's numbers, 140 million people and 1 trillion USD GDP short in comparison to Brazil.
That is OTL, and Perú Lost that war, The war was called War against The ConfederationCould a powerful and expansionistic Peru (which includes Bolivia) be enough to drive all these powers together in a confederation?
No? Even Today being that the Case Brazilian Diplomátic is considered second rate, their Militar muscle a Joke and their economic muscle, Even being big, Is not specially strong as is too dependant of Foreigner powers to he exercised.Only in the minds of chileans and argentineans. There was only one possible dominating power in South America, and that was Brazil. A nation encencompassing the entire south cone would still be, in today's numbers, 140 million people and 1 trillion USD GDP short in comparison to Brazil.