There is some Truth in Television to this: yes, several Nazi leaders escaped to Argentina and were allowed safe passage by the government of Juan Domingo Perón, most notoriously Adolf Eichmann (who was captured by the Mossad, put on trial in Israel, and executed in 1962) and Josef Mengele (who never did get caught but allegedly died in a scuba diving accident off the coast of Brazil in 1979). Alfred Naujocks, one of the masterminds of the Gleiwitz False Flag Operation that Germany used to justify invading Poland, was also instrumental in arranging safe passage of Nazis to Latin America. As may be seen in some of the trope write-ups on the main page, there was also a popular belief during the 1970s and 1980s that Martin Bormann, the most senior Nazi not accounted for in 1945, had escaped to South America, although it was confirmed in 1998 via DNA testing that he died in battle during the fall of Berlin. More recently, archaeologists have still turned up secret hideaways and relics
as late as 2015.
The reasons behind it, however, were not as simple as South American governments being evil and/or oblivious. Many countries sought to receive the German scientists that worked for Hitler and improve their national development. The USA, actually, got the most, including famous Wernher von Braun — although for the most part, the scientists only worked for the Nazis (and used the slave labour made available to them by the efforts of Albert Speer) because nobody else in Germany was hiring. Argentina's big "get" in this regard was aircraft designer Kurt Tank, who designed the first operational South American jet fighter for them. Argentine neutrality in World War II was not caused by popular support of Nazism, but by mere localism: for the people, it was a distant war between foreign countries, with Argentina standing to profit most by continuing to sell raw resources and manufactured goods to both sides. Other countries in South America gave Nazis sanctuary thanks to what is now a rather uncomfortable relationship between the Catholic Church (which was big in both Central Europe and South America) and fascism (which was also big in both Central Europe and South America). One hypothesis is that it was individual clergymen helping national figures escape a Communist crackdown. Another is that the Vatican was seeking Catholic bulwarks against the Communist threat — although this should not be construed to suggest that the Catholic Church approved of Nazism per se since Vatican press releases from the 1930s and '40s explicitly equated fascism with paganism and declared the swastika a perversion of the Christian cross.
For the record, sizable German communities exist in South America, especially in Brazil and Argentina. Germans have been in South America since the 16th centurynote , and the largest German communities (in Brazil, Argentina, and Chile) largely arrived in the late 19th century (well before World War II). For example, one reason The Hindenburg and other Zeppelins regularly made flights from Germany to Buenos Aires and Rio de Janeiro was to make it easier for German emigrants to visit the home country. Argentina is also home to one of the largest Jewish populations in the world.
In an ideologically inverted version of this trope, Erich Honecker, the last communist dictator of East Germany, tried to flee to South America, specifically Chile, after the fall of the Berlin Wall, when he was charged in connection with deaths there, by hiding in the country's embassy in Moscow. His wife, Margot Honecker, had already fled to Chile. He was ultimately ejected and returned to the reunified Germany, where legal proceedings were terminated in January 1993 on grounds of his having terminal liver cancer, after which he finally made it to Chile. After his death in May 1994, his widow stayed in Chile and remained a staunch Stalinist all the way to her death in 2016. Another inversion of this trope is Oskar Schindler, who famously bankrupted himself by using his factory to save Jews threatened by The Holocaust, lived in Argentina for most of The '50s to seek his fortune, albeit failing to find it, and returned to Germany afterwards and suffered further business failures and spent the rest of his life in poverty, barely subsisting on donations by Jews grateful for him saving them.
