George Pearse Guerrier was born on March 1, 1837, in London, England, to Samuel and Mary Guerrier. He grew up in Islington, England. He eventually immigrated to America and settled in Massachusetts. By the early 1860s, he was working as a gardener.
He enlisted in the Union army on September 13, 1861, and he mustered in as a private in Company B of the 22nd Massachusetts Infantry. According to his service records, he was 5 feet, 7 ½ inches tall, with light hair and blue eyes. The regiment took part in the Peninsula campaign. He was wounded in the face in the Battle of Gaines’ Mill on June 27, 1862, and Confederates captured him soon afterward. He received a parole in July 1862, and he spent the next few months recovering. In November 1862, a surgeon reported that he was suffering from “symptoms of morbus brightii.” He was discharged on December 8, 1862.
In early 1864, he received a commission as a 2nd lieutenant in Company A of the 35th USCT Infantry. The regiment took part in the Battle of Olustee. He was discharged for disability on August 10, 1864.
He returned to Massachusetts after leaving the army. He applied for a federal pension in March 1866 and eventually received one. He married Emma Ricketson on September 2, 1867, and the couple apparently had no children. They lived in New Bedford, Massachusetts, and he earned a living as a railroad engineer. By 1870, the family owned $1,000 of personal property.
He moved to Boston, Massachusetts, in the 1870s. In 1891, abolitionist William Lloyd Garrison petitioned the Massachusetts legislature to provide relief to Guerrier. By 1910, he was living in Belmont, Massachusetts. He died there of “senile dementia” on July 13, 1911.