Under which plan were the Southern states divided into military districts governed by Union armies?

The correct answer is that the Southern states were divided into military districts governed by Union armies under the Military Reconstruction Act. This Act, passed in 1867, aimed to implement a more stringent Reconstruction process after the Civil War. It established five military districts in the South, each overseen by a Union general, to maintain order and enforce laws, particularly those related to the rights of newly freed African Americans.

The Act was significant in that it required states to create new constitutions guaranteeing African American men the right to vote, and it set conditions for Southern states to rejoin the Union. The military presence was necessary to protect these rights and to suppress any potential violent resistance from Southern whites who opposed Reconstruction policies.

The other options relate to aspects of Reconstruction but do not involve the military governance of Southern states to the same extent. The Proclamation of Amnesty granted pardons to former Confederates and encouraged the reintegration of Southern states without military divisions. Johnson's Reconstruction Plan was more lenient towards the South and did not involve a military framework. The Reconstruction Act of 1867 encompasses the Military Reconstruction Act but is a broader legislative effort that included several components, rather than specifically referring to the division into military districts. Thus, the focus on military governance distinctly identifies