Boyle was born and raised in Mercer County (now
Boyle County, Kentucky), and graduated from the
College of New Jersey in 1838. He was the son of Judge and Chief Justice
John Boyle, for whom Boyle County was named. He then studied law at
Transylvania University in
Lexington, Kentucky. He became a successful lawyer in
Harrodsburg and
Danville. Although a slave-owning
Whig politically, he argued for a gradual
emancipation of slaves as a delegate to the
State Constitutional Convention in 1849. He married Elizabeth Owsley Anderson of
Garrard County and raised seven children. For a number of years, he was engaged in business with his brother-in-law,
William Clayton Anderson, a former
United States Congressman. Boyle supported the
Constitutional Union Party in the election of 1860. At the outbreak of the Civil War, Boyle raised a
brigade of
infantry for service in the Union Army. He was commissioned as a brigadier general on November 19, 1861. After wintering his troops in Tennessee, he joined
Maj. Gen. Don Carlos Buell's
Army of the Ohio and participated in the
Battle of Shiloh. In May 1862, he was appointed Military Governor of
Kentucky by
President Abraham Lincoln, and at times served in command of both the
District of Kentucky and
District of Western Kentucky. Curiously, the
Official Records refer to Boyle's command as the "District of Western Kentucky", although at that time it included all of Kentucky
except Western Kentucky, which was assigned to the
District of Columbus. Boyle dispatched troops several times to combat incursions and cavalry raids by
John Hunt Morgan. He resigned in 1864 after his son, the Union Army's youngest colonel, Col. William O. Boyle, was killed in action at the
Battle of Marion in
Tennessee. He had been affectionately known as "the Boy Major." Following his return home, Boyle speculated in land and became interested in street railways and urged Louisville officials to establish such service. In 1865, he became the president of the
Louisville City Railway Company and oversaw the creation of the first
mass transportation system in the commonwealth. He was president of the
Evansville, Henderson and Nashville Railroad from 1866 until his death in 1871. He traveled to
Europe and secured French investors to back a project to expand narrow-gauge rail service in Kentucky. Boyle died on July 28, 1871, in Louisville and was buried in
Bellevue Cemetery in Danville. ==See also==