Confederate Gen. Robert E. Lee wrote this week 150 years ago in the Civil War to the president of the Confederacy as his battered army continued its recovery from defeat at Gettysburg.

Both North and South had experienced heavy bloodletting in the fight and were bidding to regroup after what would turn out to be the pivotal battle of the war.

In a letter dated July 31, 1863, Lee told Confederate President Jefferson Davis that the adverse turn of events at Gettysburg for the South cannot be blamed on anyone but himself.

“No blame can be attached to the army for its failure to accomplish what was projected by me, nor should it be censured for the unreasonable expectations of the public. I am alone to blame, in perhaps expecting too much of its prowess & valour,” Lee wrote Davis.

In the same letter, Lee added: “Our loss has been heavy, that of the enemy’s proportionally so.” And he concluded that his plan could have worked if all the elements of his war strategy had come together as expected: “I still think if all things could have worked together it would have been accomplished.”

Many letters were going back and forth between Davis and Lee at this point in the war, with Davis at the time promising to rapidly furnish more fighters for the badly depleted Army of Northern Virginia.