The personality traits that helped Grant win the Civil War were ones that he exhibited throughout his life, from his childhood and youth to his two terms in the White House and retirement career as a diplomat and author. Each trait represented a strength, as well as a weakness.
Courage
Grant displayed a consistent lack of concern for his own safety not just in ordinary battlefield leadership but in patently dangerous situations, which sometimes seemed careless.
Modesty
In contrast to Winfield Scott, McClellan and other Union generals who reveled in military display, Grant rarely planned for pomp and ceremony and even actively tried to avoid the appearance of boasting.
Any ambition Grant had during the war didn’t run towards external goals like setting himself up for a career in politics or business. Instead, Grant was laser focused on defeating the enemy’s armies, right up through Appomattox, and even as army commander, Grant was not above taking on even lowly tasks himself necessary to achieve victory.
Good Judgment
Grant was not awed by the pretentions of orthodox military leaders like General Henry Halleck, known as “Old Brains,” who was smart about war sitting behind a desk from dumb about war standing on a battlefield.
By the end of the war, Grant sidelined Halleck and other impressive but ineffective commanders, and then compiled a dream team of war leaders including Sherman and Sheridan who shared Grant’s philosophy of targeting armies and not territory, and relentlessly following attack with attack.
He would also rather spend time with his family than with either soldiers or politicians, which says something about Grant’s priorities.
Intelligence
Grant was able to see the war as if from the air, beyond battlefield tactics in any one contest to war strategy across theaters. This was one way he was superior to Robert E. Lee, who succeeded when he focused on Virginia but failed when trying to take the fight into the enemy’s home territory, as in the Confederate attacks at Antietam and Gettysburg.
Bias for Action
Grant was always impatient to act, to follow up a victory not with rest but with additional attacks. He even had a superstition of going backward along the same road he’d already traveled.
Innovation
The first modern general in what became the first modern war, Grant skillfully used new technologies like the telegraph to conduct a coordinated war effort across a continental spread. After initial doubts, Grant also came to accept and then embrace the innovation of emancipation and employing freed slaves as soldiers and laborers both to deprive the enemy of their labor and to add their help to the Union forces.
Compassion
Hardly the butcher that his critics claimed, Grant hated killing and was saddened by his deaths of both friend and foe alike, especially from disease in camp. To minimize wartime deaths, Grant sought to bring the war to an end as quickly as possible.