The War of the Triple Alliance happened as per OTL; the knock-on effects of an altered Sarawak wouldn’t hit Europe or the Americas until the 1870s. However, the War of the Pacific did have a few quibbles. Chile took Antofagasta, Bolivia’s Litoral department and even Peru’s Tacna and Arica districts outright, instead of occupying the latter areas IOTL with a plebiscite promise. This has led to very sour relations amongst the three countries – Peru losing her best southern ports and Bolivia now a landlocked country – and there is high anti-Chilean sentiment with Peruvians and Bolivians.
With the Great War rolling, the jealousy has only intensified. Now that wealth of the Atacama Desert is clear for all to see, there are some murmurings on how unfair only one nation gets to exploit the world’s demand for nitrates. In any case, the boom in northern Chile is sucking up immigrants from Bolivia and Peru, which is also a good thing (more workers) and a bad thing (more workers – from neighbors who bear a grudge).