Buford engages Heth
A common yarn that was told was that the battle began because Harry Heth needed shoes for his men and wanted to go into Gettysburg to get them. That is false. Jubal Early’s men had been through a few days before and cleaned the town out and Heth knew that, and if Heth didn’t his superior A.P. Hill did. Robert E Lee found out that the Union army was closer at hand than anticipated and needed to concentrate his army, either at Cashtown or Gettysburg. Since he lacked competent cavalry at hand Heth was sent forward in a reconnaissance in force. to scout what was in Gettysburg and its vital road network. His men had encountered Union cavalry the day before and had retreated as ordered. Heth believed that at worst it was an advanced scouting party and he could brush them aside easily but he was under orders not to bring on a general engagement. Whoops.
That Union cavalry was under the command of John Buford, one of the most competent Union cavalry commanders of the war. Heth believed that it was only an advanced party but Buford was here in force, two brigades of about 2,500 men (minus one out of every four men who had to hold the horses) and one battery of artillery. Buford recognized that the terrain near Gettysburg was good defensive ground and he also knew that Union infantry was nearby. If he could just hold long enough the infantry could arrive.