Seth Ingram, surveyor, merchant, and public official, was born in Vermont on June 19, 1790. During the War of 1812 he served as a sergeant in the Eleventh Regiment, United States Infantry. On April 26, 1822, he and his brother Ira Ingram, a Nashville, Tennessee, bookstore proprietor, became co-owners of a single share of stock in the newly organized Texas Association. That same year Seth arrived in Texas with letters of introduction and recommendation as a surveyor from Joseph H. Hawkins of New Orleans. He was engaged by Stephen F. Austin as a surveyor for his colony in August 1823 and platted the town of San Felipe de Austin in late 1823 and early 1824. For such work he was paid at the rate of five dollars a mile in property or three dollars a mile in cash. Ingram took part in colony elections in August and December of 1823 and April of 1824. In the summer of 1824 he served as first lieutenant in the colonial militia. As one of Austin's Old Three Hundred colonists, on July 29, 1824, he received title to two leagues and one labor of land that later became part of Wharton and Austin counties; six years later he obtained an additional league near Matagorda Bay in what became southwestern Matagorda County. By 1827 Seth and Ira had formed a partnership with Hosea H. League to operate a general store in San Felipe. This establishment stood near Stephen F. Austin's cabin on the banks of Bullinger's Creek a half mile west of the Brazos River.
Late in the summer of 1830 Ira Ingram quarreled with John G. Holtham, a lawyer of unsavory reputation, over Holtham's drunken intrusion into Ingram's yard. Holtham demanded an apology for being expelled from the premises. When Ira ignored him, he circulated handbills defaming Ira as a "coward, a rogue, and a man without honor." On September 2, 1830, Seth Ingram confronted Holtham as he was posting one such notice in the streets of San Felipe and ordered him to remove it. When Holtham refused, pistols were drawn, and Ingram killed Holtham. Ingram was arrested along with Hosea League, who had been a bystander during the incident, and both were confined almost incommunicado for sixteen months, much of the time in heavy irons. As the municipality had no jail, the two were chained to the walls of the half-completed meetinghouse of the San Felipe ayuntamiento. With the colony's inherently cumbersome legal machinery moving at a suspiciously lethargic pace, frustrating the adjudication of their case indefinitely, the pair were finally released on bond in January 1832 but were arrested again a short time later after a murder in the colony.
Although in the estimation of Stephen F. Austin, Ingram was as fine a citizen as could be found in the colony, League was reportedly a very unpopular man with few friends and many influential enemies. In the fall of 1831, however, more than 700 signatures were obtained on a petition for the prisoners' release. During his confinement Ingram wrote to Austin requesting additional grants of land to alleviate his financial distress, pointing out that his work as a surveyor had profited the colony, while he himself had been forced into poverty through long imprisonment. At last, sometime in late 1832, the pair were tried, acquitted, and released. In December of that year Austin directed Ingram to survey a league on Karankawa Bay for Sam Houston.
By 1834 the Ingram brothers had moved to Matagorda, where both were members of the Committee of Safety and Vigilance in September 1835. Seth served as one of the executors of his brother's estate in October 1837. As a justice of the peace he appears to have officiated at his own marriage to Susanna Rice on December 5, 1837. He was one of the trustees of Matagorda University upon its incorporation in February 1845. According to Matagorda County marriage records, Ingram took Sarah M. Davis as his second wife on February 9, 1846, and less than four years later, on December 24, 1849, he wed Mary E. Carter. The census of 1850 described Ingram as a notary public owning $2,000 in real property, while his wife Mary held an estate worth $10,000. Ingram died on May 12, 1857, and was buried at Matagorda.