What was one major accomplishment of the Freedmen's Bureau? establishing the National Equal Rights League registering new voters for the Democratic Party forming African American colleges and universities overturning the Black Codes in the South

One major accomplishment of the Freedmen's Bureau was forming African American colleges and universities.

Explanation:

The Office of Refugees, Freedmen and Abandoned Lands, commonly referred to as the Freedmen's Bureau, was an agency of the United States Federal Government whose purpose was to assist African Americans affected by the Civil War.

The Freedmen's Bureau Bill, which created the Freedman's Bureau, was promulgated by President Abraham Lincoln and was expected to last a year after the end of the war. On March 3, 1865, the United States Congress authorized its creation.

This office instituted day-to-day duties, providing daily rations and clothing to former slaves who had no money. It also built schools and churches: 4,000 schools were built, as well as an African-American university in Atlanta.

The answer is: forming African American colleges and universities