Final answer:
Federal officials responded to the Black codes in 1866 by passing the Civil Rights Act and reinforcing the Freedmen's Bureau, ensuring federal protection for African Americans' rights.
Step-by-step explanation:
In 1866, Federal officials took action against the Black Codes enacted by southern states after the end of Reconstruction. They passed the first Civil Rights Act, which established the citizenship of African Americans and gave the federal government the authority to intervene in state affairs to protect citizens' rights.
President Johnson vetoed the Act, but Congress overrode the veto. Although the Black Codes persisted and formed the basis of Jim Crow segregation policies, the actions of Federal officials marked an important step in protecting the rights of African Americans.