Following the final collapse of South Vietnam in 1975, the U.S. evacuated some 130,000 Indochinese — Vietnamese, Cambodians and Laotians — fleeing the new Communist government. Americans were deeply divided on whether these refugees should be allowed to live in the United States: In a May 1975 Harris poll, for example, 37% were in favor, 49% opposed, and 14% weren’t sure. Nonetheless, the refugees were allowed to stay.

Later in the decade, hundreds of thousands of people living in Vietnam (including many ethnic Chinese) began leaving the country in overcrowded boats. At the same time, thousands of Cambodians and Laotians were escaping their countries over land. In response to the humanitarian crisis, President Jimmy Carter in June 1979 doubled the number of Indochinese refugees the U.S. had previously agreed to accept, to 14,000 a month. The move was not popular: In a CBS News/New York Times poll the following month, 62% disapproved of Carter’s action. But between 1980 and 1990, according to federal immigration data compiled by Pew Research Center, nearly 590,000 refugees from Vietnam, Cambodia and Laos were admitted into the U.S.