George Hillyer (March 17, 1835 – October 2, 1927) was an American politician, serving as the 29th Mayor of Atlanta, Georgia, as well as a state assemblyman and senator. He was also an officer in the Confederate States Army during the American Civil War.
Hillyer was born in Athens, Georgia, one of eight children of Judge Junius Hillyer, a United States Congressman and solicitor of the U.S. Treasury. He graduated from Mercer University in 1854, studied law, and, starting in 1857, served two years in the Georgia General Assembly. He was a delegate to the 1860 Democratic National Convention in Chicago, Illinois. He married Ellen Emily Cooley, and raised a family.
With the outbreak of the Civil War, he raised a Walton County company known as the "Hillyer Rifles" in the late spring of 1861. The men were mustered into the Confederate Army on June 13, with Hillyer elected as the captain of Company C of the 9th Georgia Volunteer Infantry. He and the regiment were sent by train to Virginia and assigned to the newly created brigade of George "Tige" Anderson in what became the Army of Northern Virginia. Hillyer saw extensive fighting at Fredericksburg (briefly commanding the regiment) and Gettysburg, where he fought at the famed "Wheatfield" on July 2, 1863. The 9th Georgia lost half of its 340 men in the fight, and Hillyer's company suffered considerable losses. With all the senior officers wounded or killed, Hillyer assumed command of the regiment for the rest of the Gettysburg Campaign, and wrote the official report of the 9th Georgia's service in the battle.