William Edward Petty Hartnell

William E. P. Hartnell
Guillermo Arnel
Portrait by Leonardo Barbieri, 1853
Born(1798-04-24)April 24, 1798
Backbarrow, England
DiedFebruary 2, 1854(1854-02-02) (aged 55)
CitizenshipUnited Kingdom United Kingdom
Mexico
United States United States
Known forNamesake of Hartnell College
Spouse
Teresa de la Guerra
(m. 1825)
Children25
RelativesJosé de la Guerra y Noriega (father-in-law)

William Edward Petty Hartnell (April 24, 1798 – February 2, 1854), later known by his Spanish name Don Guillermo Arnel, was a merchant, schoolmaster, and government official in California. He arrived in California in 1822 as a trader, where he married into the prominent Guerra family of California and became a Mexican citizen. He held several public roles during the Mexican era and after the American Conquest of California, notably serving as the official translator at the Monterey Constitutional Convention.