Herman Ehrenberg, surveyor and cartographer, survivor of the Goliad massacre, writer, and engineer, was probably born in the village of Steuden, Prussia, where the birth of a Hermann Vollrath Ehrenberg was registered on October 17, 1816, at the Lutheran church. Sources differ as to the identity of his parents. He may have been the son of William von Ehrenberg, a Prussian royal official, or his parents may have been Johann and Sophie Ehrenberg. Many historians state that Ehrenberg was a Jew; if he was, the reason for registry of his name in a Lutheran church is not clear. He immigrated to New York in 1834, then in October 1835 joined the New Orleans Greys at the encouragement of Nicholas Adolphus Sterne. He went to Nacogdoches, fought in the siege of Bexar in early December 1835, and, after spending the winter inside the Alamo getting supplies for the army, set out from San Antonio toward Goliad with a number of men in the Greys. It was their goal to eventually march to Matamoros; however, the group ended up staying under James W. Fannin's leadership. Ehrenberg recorded his account of Fannin's actions and the subsequent battle of Coleto, where the Texan forces surrendered to Gen. José de Urrea. The Mexicans offered all Germans the opportunity to join the Mexican cause, but Ehrenberg stated that he considered himself a Texan and refused the offer. A week later he was one of a few men who escaped the Goliad Massacre. According to a translation of Ehrenberg's own account, after the command to kneel and the start of the shooting, he jumped up and, hidden by the gunsmoke, dashed for the San Antonio River. On the way a Mexican soldier slashed him in the head with his saber, but Ehrenberg managed to get by him and jumped in the river crying, "The Republic of Texas forever!" For several days he traveled through the prairies, finding shelter in a couple of abandoned plantation houses along the way, but finally he reasoned that the only way to survive would be to surrender to General Urrea. Ehrenberg posed as a Prussian traveler seeking protection, and Urrea, admiring the boy's daring action, took in the "little Prussian." Ehrenberg was taken with Urrea's troops to Matagorda, and after news of the battle of San Jacinto he eventually reached freedom. He was discharged from the Texas army on June 2, 1836. He received a certificate for part of a league of land but never personally claimed it. In 1880 the land was awarded to his heirs from Teplitz, Bohemia.
Ehrenberg then returned to Germany and studied mining at Freiburg University. In the early 1840s he was an English teacher at Halle University. He came back to the United States in 1844 and traveled from St. Louis to Oregon with a fur-trapping party. In May 1845 he sailed from Oregon to Hawaii, where the government employed him to survey streets and draw a map of Honolulu. He also visited a number of Polynesian islands, including Tahiti. Ehrenberg was in California in time to participate in the Anglo-American conquest of 1846–47. He helped rescue Americans held captive in lower California during the Mexican War. He took part in the California gold rush in 1848–49. He traveled to the Gadsden Purchase in 1854 and made the first map of the purchase. In 1855 he surveyed and helped incorporate the town of Colorado City, Arizona. In 1856, with Charles Poston, Ehrenberg established the headquarters of the Sonora Exploring and Mining Company at Tubac, Arizona, and was appointed surveyor and mining engineer. Senator Barry Goldwater called Ehrenberg "one of the greatest surveyors and map makers ever to visit the Western United States." He was also an Indian agent for the Mojaves on the Colorado River Reservation from 1863 to 1866. The United States Board of Geographic Names gave the name Ehrenberg Peak to a summit in Grand Canyon National Park.
During his lifetime Ehrenberg compiled a number of maps including "Map of the Gadsden Purchase, Sonora, and portions of New Mexico, Chihuahua & California," in 1854. He wrote articles for Mining Magazine and Journal of Geology and Arizona Weekly. His other published works include an account of the battle of Coleto and the Goliad massacre. He named the first (1843) edition of his book Texas und seine Revolution. The 1844 edition was called Der Freiheitskampf in Texas im Jahre 1836, and the book was published again in 1845 as Fahrten und Schicksale eines Deutschen in Texas. In 1925 Edgar William Bartholomae translated the 1845 edition into English as a master's thesis at the University of Texas. In 1935 Henry Nash Smith edited a translation by Charlotte Churchill for children entitled With Milam and Fannin: Adventures of a German Boy in Texas' Revolution. This version was reprinted in 1968. Texas und Seine Revolution is one of John H. Jenkins's Basic Texas Books.
Ehrenberg never married. He was murdered by robbers on October 9, 1866, at Dos Palmas, near the site of present Palm Springs, California. Mineral City, Arizona, was renamed Ehrenberg in his honor through the efforts of Michael "Big Mike" Goldwater.