Hi David! Greetings from Buenos Aires! Thanks so much for showcasing my country!
First two quick fixes: 1) our neigbourgh is Chile (no Chili) 2) Argentina does have an official language which is Spanish - all official documents were always and are produced in Spanish. The latest upgrade of our local magna carta recognizes though other locally spoken languages:
These were included to allow bilingual education rights in certain places.
As for genealogical sources, they haven't been massively digitalized so they're difficult to access. Civil records across the nation were introduced as far as 1880 but they were never centralized. Some provinces are digitalizing their databases through FamilySearch, but sadly the 2 bigger ones (Buenos Aires Province and City of Buenos Aires) are not so far. There's are some church records though in FS, that go back to colonial times.
A quick 3rd note: Buenos Aires was a single entity until about 1880, when the growth in population, the expansion of the colonized territory and geopolitical strategy coalesced in the separation of it in 2 entities: a) City of Buenos Aires, which became the political capital (name: Ciudad de Buenos Aires/Capital Federal) with no elected authorities until 1996 in which it became an autonomous city (current name: Ciudad Autonoma de Buenos Aires shortened as CABA - great article showing the evolution of the city here: https://www.geografiainfinita.com/2018/06/la-evolucion-de-buenos-aires-a-traves-de-los-mapas/) and b) Buenos Aires Province, for which a new capital city was founded and built from scratch: La Plata (about 50km from Buenos Aires city) .
For immigrating people, there're several databases that can be accessed:
- http://www.entradadepasajeros.com.ar/ for 19th century immigration
- https://cemla.com/ for the main immigration period, about 1880 to 1945, in which european immigration was favored.
After around 1945/50 we also received big waves of immigrants from our neighboughring countries (Paraguay, Bolivia and Peru mainly), some asian (from Japan after WWII, later from China and Corea after 1980') and the latest to arrive are a lot of exiles from Venezuela.
I hope this helps. Thank you again!