Starting at the age of 14, he attended nearby Jefferson College in Canonsburg, Pennsylvania, studying civil engineering and law, but was forced to leave before graduation due to the death of his father, whose debts he assumed.
He worked at a variety of jobs, including as a surveyor and land speculator in Kentucky, earning enough to return to college and graduate in 1841.
[3] Geary was an excellent target for enemy fire: a huge man for that era, he stood six feet six inches tall, 260 pounds (118 kg) and solidly built.
[5] Proslavery forces opposed Geary, favoring instead either acting governor Daniel Woodson or Surveyor General John Calhoun (an Illinois politician).
He believed that his previous administrative experience in government would help bring peace to the territory, but he was unable to stop the violence.
Geary wrote in his response, "[there is] doubtless some suffering ... consequent upon the past disturbances and the present extremely cold weather; but probably no more than exists in other territories or in either of the states of the Union.
By the time of the 1856 presidential election, however, he had completely reversed his position and had become intimate friends with Charles Robinson and Samuel Pomeroy.
Instead, he worked with the Free-staters to create a plan for Kansas to be admitted to the Union under the Topeka constitution as a free state, with himself as governor of a Democratic administration.
[8] Geary soon began to fear for his personal safety after his private secretary, Dr. John Gihon, was assaulted by proslavery ruffians.
[10] Commanding the district of the upper Potomac River, he was wounded and captured near Leesburg, Virginia, on March 8, 1862, but was immediately exchanged and returned to duty.
At the Battle of Gettysburg, Slocum's corps arrived after the first day's (July 1, 1863) fighting subsided and took up a defensive position on Culp's Hill, the extreme right of the Union line.
On the second day, heavy fighting on the Union left demanded reinforcements and Geary was ordered to leave a single brigade, under Brig.
Geary lost track of the division he was supposed to follow south on the Baltimore Pike and inexplicably marched completely off the battlefield, eventually reaching Rock Creek.
This embarrassing incident might have damaged his reputation except for two factors: the part of the battle he was supposed to march to join had ended, so he wasn't really needed; and, because of a dispute between army commander Maj. Gen. George G. Meade and Slocum over the filing of their official reports, little public notice ensued.
He oversaw the surrender of Savannah, Georgia, and briefly served as the city's military governor, where he was breveted to major general.
On February 8, 1873, less than three weeks after leaving the governor's post, Geary was fatally stricken with a heart attack while preparing breakfast for his infant son in Harrisburg, Pennsylvania.
Geary was made a Mason at Sight on January 4, 1847, in Pennsylvania (Philanthropy Lodge #255), just before he left with his troops to fight in the Mexican War.
I feel again justified in referring to our beloved institution, by saying that to Freemasonry the people of the country are indebted for many mitigations of the suffering caused by the direful passions of war.