As the 1850s drew to a close, and the debate over slavery
degenerated into war, Garfield began to shift away from teaching
and to pursue his new interest in politics. He cast his first vote
for president in 1856 for the Republican candidate, John C. Fremont,
and even made several pro-Republican speeches in and around Hiram.
In 1859, on top of his classes and his duties as principal
of the Western Reserve Eclectic Institute, Garfield began studying
law. He joined the Cleveland Law Firm of Williamson and Riddle
as a student-at-law, and two years later, just before the Civil
War began, Garfield passed the Ohio bar exam.
In 1859, Garfield easily won the Republican nomination
for state senator and entered the senate in 1860 at the young age
of twenty-eight. Garfield became interested in tax revenue and
state appropriations, which lead him to become one of the senate's
top fiscal legislators.
The upcoming war, however, soon overshadowed all other debate.
Garfield opposed a Constitutional amendment
that would have prohibited Congress from interfering in slavery
issues. By the end of the term South Carolina had seceded and the
Ohio governor, Salmon P. Chase, had left to become Abraham Lincoln's
treasury secretary. The state began to mobilize for war.
Lincoln's election in 1860 had set in motion a series
of events that catapulted the United States into civil war. A dozen
dissident states seceded from the union to form the Confederate
States of America, and the two sides fought the first battle of
the Civil War at Bull Run. As 1861 dragged on, both sides mobilized
for a long war, although neither side had any idea how long and
how costly the war would become.
When the legislature adjourned for the year, Garfield
offered his services to the state militia. Although he was completely
untrained, the governor granted Garfield a commission as lieutenant-colonel of
the forty-second regiment of Ohio volunteers on August 14, 1861.
As he often did when entering a new endeavor, Garfield began a
quick study of military strategy, then set about developing a four-month
drilling regimen for his men at Camp Chase near Columbus, Ohio.
On December 15, 1861, Garfield presented his newly-trained soldiers
to the Union high command at Louisville. When Confederate troops
overran eastern Kentucky, Garfield was promoted to the command
of the Eighteenth Battalion, and although this assignment greatly
exceeded Garfield's experience, he applied the same quick learning
style and easy-going manner that had worked so well for him in
school, and proved himself to be an excellent soldier.
Garfield was assigned the task of removing the army of
Confederate General Humphrey Marshall from eastern Kentucky. Marshall,
who had trained at West Point, had almost twice the number of troops
as Garfield, as well as the support of many citizens of Kentucky.
Garfield rapidly moved his force across the state and, by using
the element of surprise, kept Marshall's forces off-balance. Marshall
eventually abandoned his position and, leaving many of his supplies
behind, began to retreat. Garfield's forces caught up with Marshall
and managed to stall him until reinforcements arrived. On January
12, 1862, Marshall's line broke and Garfield won the battle. The
victory was one of the few battles that the Union won in this early
phase of the war, and President Abraham Lincoln
promoted Garfield to major-general of volunteers, making him the
youngest commander in the Union.