Want this question answered?
Assuming you mean First Bull Run... It demonstrated that neither side was ready for combat, and that it wasn't going to the short war that everyone had hoped for.
B
The Battle of Malvern Hill, fought on July 1,1862, and that of Gettysburg, during the third day, demonstrated the importance of this.
Neither side was ready for operations, as demonstrated at the First Battle of bull Run. They still had to recruit, train and equip large armies.
No, the deadliest battle of the Civil War was that of Gettysburg.
The Battle of Antietam was not a clear victory for neither the Confederate nor the Union armies.
The Battle of Gettysberg
The battle of Peters burg was one of the last battles of the Civil War. Neither the North or the South won.
The Union won this battle.
The battle of Gettysburg.
The Battle of Hampton Roads.
The Battle of Antietam (Battle of Sharpsburg) .