Here in the United States we are very used to seeing descriptors such as “Italian-American”, “Japanese-American”, “Irish-American” and so forth, used not only do describe immigrants, but their descendants as well.
Other than Canada and Israel, I don’t know of any significant American immigration to another country. I am not talking about temporary expatriates, retirees, ‘tax exiles’, or actors who have a summer home in France, but American born naturalized citizens of another country who are notable for their achievements in that country.
The only examples of famous American emigrants I can think of are T.S. Eliott in the United Kingdom, Queen Noor of Jordan, Princess Grace of Monaco, and Eamon de Valera in Ireland. Are there any other examples? Perhaps American born people who are unknown or obscure in the United States but well known in their adopted country.
Valdas Adamkus was born in Lithuania, emigrated to the U.S. in his youth to escape the Soviet occupation of his country, became a U.S. citizen (and an official in the EPA), then moved back to Lithuania after the fall of communism and was elected president of that country (renouncing his U.S. citizenship in favor of Lithuanian citizenship).
William Walker born here in Nashville TN, tried to annex the Baja pennisula for the USA but was defeated by the Mexican military and run back across the border. He then went to central America and became president of Nicaragua by force of arms, making the critical mistake of running afoul of the Vanderbilts when he seized one of their railroads. With Vanderbilt’s backing a coalition of neighboring nations ousted him from power and sent him packing back to the States. He then tried AGAIN to go south where he ended up being shot by a firing squad in Guatamala.
The American singer Dean Reed (bio ) lived and worked in East Germany from 1973 until his death in 1986. His biography does not mention his getting naturalized in East Germany but the East German government would have been delighted to extend citizenship to him. It seems he did retain US his citizenship.
Of course, having become “notable” in Britain, Mrs. Simpson had to immediate leave to live in France.
Nancy Astor, the first woman to take her seat in the House of Common in Britain, was American by birth.
Sam Wanamaker was fairly well known as an actor when he left the US for Britain in the McCarthy era, but he’s best remembered for his successful campaign to reconstruct the Globe Theatre in Southwark.
There are always a number of UK-specific showbiz personalities who originate from America and are thought of as American even though they live and work here - obvious current examples would be Ruby Wax and Lloyd Grossman.
Golda Meir, Prime Minister of Israel, was born in Milwaukee.
Jennie Jerome, daughter of a millionaire American financier, went to England in the 1870s and fell in love with the second son of the Duke of Marlborough. They married and she spent the rest of her life in Britain, where she was, variously, mistress of the Prince of Wales and a leading member of high society. But most notably, she had two sons, of whom the elder was the second man (after the Marquis de Lafayette) ever to receive honorary citizenship from the U.S. by act of Congress – Sir Winston Leonard Spencer Churchill, K.G., Prime Minister of the U.K. 1940-45 and 1951-55.
Golda Meir - originally from Kiev, but raised in Milwaukee. Was prominent for many years in Israeli politics, ultimately becoming Prime Minister of Israel in 1969.
No, Paul Robeson never lived in the Soviet Union for very long. He made public statements in favor of the Soviet Union several times. He once had his American passport taken away. But he never gave up his American citizenship and he died in the U.S. Here’s a biography:
W. E. B. Du Bois (1868-1963), one of the most illustrious African-American thinkers, a major prophet of Black liberation, author of The Souls of Black Folk. He lived a long, long life and shortly before he died he moved to Ghana as it achieved independence and became a Ghanaian citizen.
That actor, what’s his name? Mel Gibson? The Mad Max guy? He was born in the United States but moved to Australia as a child and became famous as an Australian. This allows him to talk either American or Australian with equal facility, a handy talent in an actor.
Two more African-Americans who had to leave their birthland because of racism to achieve success overseas:
Ira Aldridge (1807?-1867) — a celebrated actor, the original prototype for Paul Robeson. He was welcomed in England as he never could have been in America. His portrayal of Othello brought down the house. He became a British citizen.
Josephine Baker (1906-1975) — Born in St. Louis, she was a smash hit at the Folies-Bergère and was the toast of Paree in the roaring '20s. America rejected her but Europe loved her and she loved Europe in return. She worked for the French Resistance in WWII and was awarded the Legion d’Honneur for her services to France. She also worked for the Civil Rights movement in America after the war.
How about the folks that started Liberia? They’d surely count, I’d think. Also a number of African-Americans at various times have gone back to Africa and held important positions, IIRC.