During the 1920s, many famous Americans (such as F. Scott Fitzgerald and Ernest Hemingway) went to Paris. Did Americans in America see these expats as "unAmerican" as they might been seen, today?
No, it,was seen as a "classy" thing to do. Plus there was the added bonus of being able to drink legally unlike in the US.
Hemingway was only in Paris for about a year and a half. He was there working as a foreign correspondent for the Toronto Star newspaper. He covered the war between Greece and Turkey and left Paris several times during his stay there to visit the war zone. He published over 80 articles during that time period.
Fitzgerald was already a very successful author and could support himself. He lived in France with his wife Zelda for about seven years.