Daniel Sickles was an infamous figure even before the war began.  Sickles is notorious for his role in the Battle of Gettysburg, a role that was debated between generals and officers after the war, a debate that continues today.  The III Corps under Sickles arrived at the battlefield over a period of time from the evening of July 1 after the fighting had calmed for the day into the morning of July 2.  Meade intended the corps to extend his line along Cemetery Ridge, attaching themselves to the end of the II Corps line and ending at the base of Little Round Top.  Whether Sickles misunderstood his orders or willfully disobeyed them, the III Corps ended up in another position entirely.