https://2012-2017.usaid.gov/who-we-are/usaid-history
When the United States Agency for International Development (USAID) was created, it brought together several existing foreign assistance organizations and programs. Until then, there had never been a single agency charged with foreign economic development, so with the passage of the Foreign Assistance Act of 1961 (pdf) by Congress, U.S. foreign assistance activities underwent a major transformation.