Question

In the Battle of Gettysburg, how did Lee hope to protect Pickett's charge?

Answer 1

Lee ordered a artillery barrage to weaken the Union Line on Cemetery ridge. The cannons were to continue to fire until just before the infantry reacher the Union lines.

Explanation:

The artillery fire was designed to cause severe casualties in the Union forces on the ridge.

The tactic didn't work. Most of the Cannon fire went over the heads of the union forces. Unknown to Lee there were substantial reserve forces that were resting behind the ridge undamaged by the artillery fire.

Also the Confederate artillery ran out of ammunition and bringing up more ammunition was too slow and would expose the ammunition wagons to counter fire from the Union batteries.

The Confederate artillery barrage ended long before the infantry reached the ridge, leaving the infantry column exposed to artillery fire from the Union batteries.

The 15,000 infantry in Pickett's charge were decimated by artillery fire from both the front and the flanks before they reached the ridge.
When they did reach the ridge the column were meet by heavy musket fire as they climb over the fences. The Union infantry had been larger undamaged by the Confederate artillery barrage and were able to repluse the attack.