See studies by L. Hanke, ed. (1964), and W. R. Jacobs et al. (1965).
Bolton studied under Frederick Jackson Turner from 1896 and 1897. Starting in 1897, Bolton was a Harrison Fellow at the University of Pennsylvania and studied American history under John Bach McMaster. In 1899, received his Ph.D. from University of Pennsylvania and then taught at Milwaukee State Normal School until 1900.
The Carnegie Institution asked Bolton to write a report of information found about United States history in Mexican archives, and the report was published in 1913. Soon afterward, Bolton became an associate editor of the Quarterly of the Texas State Historical Association (now the Southwestern Historical Quarterly).
In 1904, Bolton and Eugene C. Barker published With the Makers of Texas: A Source Reader in Texas History, a Texas history textbook. In 1906, Bolton began studying Native American history in Texas for the U.S. Bureau of Ethnology, writing more than 100 articles for the Handbook of American Indians North of Mexico.
In 1911, Bolton became a professor at the University of California, Berkeley. There he served as the chair of the history department for 22 years and became the first director of the renowned Bancroft Library. He taught the "History of the Americas" course, which attracted up to a thousand students a week. At Berkeley he supervised more than 300 master's theses and 104 doctoral dissertations. In 1914, Bolton published Athanase de Mézières and the Louisiana-Texas Frontier, 1768-1780. A year later, Bolton published Texas in the Middle Eighteenth Century: Studies in Spanish Colonial History and Administration and declined the presidency of the University of Texas.
Over the next 29 years, Bolton published many works, including Texas in the Middle Eighteenth Century (1921), The Spanish Borderlands (1921), Outpost of Empire (1931), Rim of Christendom (1936) and Coronado (1949), for which he received a Bancroft Prize from Columbia University.
In 1932, Bolton served as president of the American Historical Association, and in 1944 retired as a professor. He taught briefly at San Francisco State College (now University) in retirement. He died of a stroke in Berkeley in 1953.
Bolton's biggest mistake was his February 1937 authentication of Drake's Plate of Brass, which was a forgery of a mythical brass plaque purportely placed by Sir Francis Drake upon his arrival in Northern California in 1579. The plate is currently on display at the Bancroft Library where he served.