Who were the radical leaders known for pushing for extreme measures during Reconstruction?

The correct choice highlights Thaddeus Stevens and Charles Sumner, who were prominent Radical Republican leaders during the Reconstruction era following the Civil War. They advocated for significant changes in the South, including civil rights for freedmen, harsh penalties for the former Confederate states, and a complete transformation of Southern society to ensure the rights and protection of newly freed African Americans.

Stevens, a Representative from Pennsylvania, was instrumental in drafting the Reconstruction Acts and sought to redistribute land to former slaves as a means of ensuring their independence and economic stability. Sumner, a Senator from Massachusetts, was a fierce advocate for civil rights and opposed any leniency towards the South, arguing for the necessity of equal rights.

The other options do not represent the radical approach to Reconstruction. Moderate Republicans sought a more conciliatory approach, while Democrats largely opposed Reconstruction measures. Frederick Douglass, while a crucial figure in advocating for African American rights, did not hold a political office in the same capacity as Stevens or Sumner, and Andrew Johnson, as a president during this period, actively worked against many Reconstruction efforts pushed by the Radical Republicans. Thus, the focus on Stevens and Sumner illustrates the core of radical leadership during this tumultuous period in American history.