My high school Spanish teacher in the mid 70s was from Madrid, so I knew a little about what had happened there in the 30s, though he never talked about it. When I was in college in the late 70s I knew a student named Roberto who was from Chile. He talked about what was going on there then, of having friends who had been disappeared, which means murdered by the government. Knowing little about South America, I just assumed that was typical of all those countries, which many Americans referred to then and now as "banana republics" (and now South Americans are saying, "Look who's talking"). Roberto educated me on that, explaining that Chile had a long history of being a stable democracy.
I mention this because I've been trying to figure out why I liked [a:Isabel Allende|2238|Isabel Allende|https://images.gr-assets.com/authors/1341879973p2/2238.jpg]'s [b:A Long Petal of the Sea|46042377|A Long Petal of the Sea|Isabel Allende|https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/books/1565211383l/46042377.SY75.jpg|69307454] as much as I did. It tells the history of both wonderfully. Whether you know lots about Spain and Chile and other events of the world from 1936 to 1994 or not, you'll like this book.
This describes what happened to the Spanish defeated by Franco as they were in a French concentration camp after fleeing Spain in 1939.

As the months went by, overcrowding in the camp gradually diminished. The old and infirm died off and were buried in a cemetery adjacent to the camp. The luckiest among the prisoners obtained sponsors and visas to emigrate to Mexico and South America. Many of the soldiers joined the French Foreign Legion, despite its brutal discipline and its reputation for harboring criminals, since anything was better than remaining in the camp. Those with suitable qualifications were recruited for the Foreign Workers Companies created to replace the French workforce called up in preparation for the coming war. Later on, others were to go to the Soviet Union to fight with the Red Army or join the French Resistance, and thousands of them died in Nazi death camps or Stalin's gulags.