Why is it that non-White people who move overseas are called "immigrants"?

Question

while White people who move overseas are called "expatriates"?

Answer 1

An expatriate is a person temporarily or permanently residing in a country and culture other than that of the person's upbringing or legal residence.  

Answer 2

Immigrants are the people who have come INTO your country; emigrants are the people who have gone OUT of your country.  Expatriates was a popular term for people who retained citizenship in their own country but who lived in another country.  It was particularly popular as a description of Brits and Yanks who lived in Europe before World War II.  None of the terms distinguished between ethnic characteristics (e.g., Billie Holliday was an expatriate).