George Mather Champney was born in New Ipswich, New Hampshire on March 6, 1812, the son of Benjamin and Rebecca (Brooks) Champney. He attended school in New Ipswich until the age of 14 when he moved to Boston to work in a retail store in the city. While in Boston, he became interested in literature, and spent much of his free time in that pursuit. At the age of 21 he returned to New Ipswich and became a partner in a country store. While there he became involved with the Appleton Academy, a lyceum and debating society.
He was married in 1836 to Lucy H. Champney and soon after moved back to Boston where he became a partner in a dry goods business. Champney continued in this business until 1847 when he formed a partnership with his brother, Edward W. Champney, under the name of Champney Brothers. In 1847 he also moved to Woburn with his family. In 1851, with the formation of the first town library, Champney served as Chairman of the Library Committee and worked to develop the library. In 1872 the Champney Brothers' firm was destroyed in the Great Fire in Boston and the business soon closed.
After Charles B. Winn's death in 1875, Champney took a leading role in planning for the new library that the town would build with the Winn endowment. He spent considerable time and energy acquiring books for the library, and became the first librarian in the new building when it opened in 1879. George Champney wrote a history of the library for the Woburn Journal in November of 1881. Less than two months later, on January 4, 1882, Champney died on the front porch of the library, at the age of 69. He was survived by his wife Lucy H. Champney, his son Edwin Graves Champney, his daughter Ellen Champney Hayden, and his brother, the artist Benjamin Champney.