John Garland was born on February 9, 1833, in Waterville, Maine, to John Garland and Mary S. Greene. His father was a farmer who owned $1,300 of real estate by 1850. He grew up and attended school in Waterville. He married Ellen Snell on December 29, 1863, and they had at least five children: Walter, born around 1865; Caroline, born around 1867; Albert, born around 1873; Mary, born around 1874; and Frank, born around 1877.
He enlisted in the Union army on October 13, 1862, and he mustered in as a private in Company B of the 21st Maine Infantry. The regiment took part in the siege of Port Hudson. He was wounded at Port Hudson on May 27, 1863, and he mustered out on August 25, 1863.
He returned to Waterville after leaving the army, and he earned a living as a farmer. By 1870, he owned $2,500 of real estate and $1,000 of personal property. They moved to Oakland, Maine, in the late 1800s. He applied for a federal pension in July 1904 and eventually secured one. He died of heart disease in Oakland on June 4, 1907.