What are facts of the first Battle of Bull Run?

Answer 1

The unfortunate Union General McDowell knew his troops weren't ready for combat, but was pushed into it by the politicans.

The Confederate General Joe Johnston ceded some authority to his junior colleague Beauregard because he had a better knowledge of the terrain, even though Johnston was a Virginian.

One of the Confederate units were wearing blue uniforms, and Union gunners thought they were friendly troops until too late, and those batteries were wiped out. (Some have cited this as the reason for Union defeat.)

The retreat to Washington was impeded by civilians who had come out from Washington to picnic beside the battlefield.