The Tenth Circuit Court of 1863 created a tenth Supreme Court justiceship, making the Court the largest it had ever been since its creation. Still, from 1863 to 1866, the complete group of ten justices sat together for just one week in December 1863. War, illness, and travel kept attendance below ten until 1866, when Congress reduced the size of the Court to nine seats.

The Tenth Circuit Court of 1863 created a tenth Supreme Court justiceship, making the Court the largest it had ever been since its creation. Still, from 1863 to 1866, the complete group of ten justices sat together for just one week in December 1863. War, illness, and travel kept attendance below ten until 1866, when Congress reduced the size of the Court to nine seats.