Holding On

• The Army of the Potomac (North) knew that the Army of Northern Virginia (South) was operating somewhere in the Northern heartland. A chance encounter between a Confederate skirmishing force looking for shoes in the town of Gettysburg and a stubborn scouting force of Northern cavalrymen, slowed the South's momentum.
  
  

High Ground

• Although the Confederates initially held the town, Union forces were able to recover and consolidate their position on higher ground.
  
  

Interior Lines

• The newly consolidated position allowed Union forces to receive significant logistical support from within their own lines. This advantage allowed a build-up of forces quickly, thereby bolstering and extending their original position.
  
  

Volume of Fire

• Once Union forces reached levels that were beyond the Confederates' ability to dislodge them, the Union volume of fire stopped Confederate momentum entirely.
  
  

Too Worn Out To Win

• Subsequently, the South wasted their power and flexibility on a series of direct attacks against Northern strength. Ultimately, these decisions broke the back of the Southern incursion. This gave Lincoln the ability to declare a victory, setting the stage for his second successful run for president in 1864--and the final defeat of Confederate forces a year later.