A son of Unitarian minister Bailey Loring and Sally Pickman (Osgood) Loring, and fourth great grandson of early settler Deacon Thomas Loring, George B. attended Franklin Academy at Andover, Massachusetts and later briefly taught school. He graduated from Harvard University in 1838 and from the Harvard medical school in 1842. He practiced medicine for a short time in North Andover. Served as surgeon of the marine hospital at Chelsea, Massachusetts (1843–1850) and as surgeon of the Seventh Regiment, Massachusetts Volunteer Militia (1842–1844).
He was appointed commissioner to revise the United States marine hospital system in 1849.
Moved to Salem, Massachusetts in 1851; appointed postmaster of Salem on May 4, 1853, and served until his successor was appointed on February 16, 1858.
He was a member of the Massachusetts House of Representatives (1866–1867); chair of the Massachusetts Republican State Committee (1869–1876); served in the State senate (1873–1876) and was also president of that body.
He was a delegate to the Republican National Conventions in 1868, 1872, and 1876; appointed United States centennial commissioner for the State of Massachusetts in 1872; elected as a Republican to the Forty-fifth and Forty-sixth Congresses (March 4, 1877 – March 3, 1881).
He was an unsuccessful candidate for renomination in 1880. Made United States Commissioner of Agriculture (1881–1885); appointed United States Minister to Portugal in 1889 and served until his resignation in 1890.
Loring married Mary Toppan Pickman (1816-1879), daughter of Dr. Thomas Pickman and his wife, Sophia Palmer Pickman, and also his cousin. His great-uncle, and his wife's uncle, was Benjamin Pickman Jr., Congressman from Massachusetts; his third cousin, once removed, and her first cousin, twice removed was George P. Wetmore, Governor and United States Senator from Rhode Island. Another great-uncle is Samuel Osgood.
- 94th Massachusetts General Court (1873)
- 95th Massachusetts General Court (1874)
- 96th Massachusetts General Court (1875)
- 97th Massachusetts General Court (1876)
|U.S. House of Representatives|
Charles Perkins Thompson
| Member of the U.S. House of Representatives
from Massachusetts's 6th congressional district
Eben F. Stone
Edward Parke Custis Lewis
| United States Ambassador to Portugal
George Sherman Batcheller