James Prentiss, businessman and land speculator, son of John and Ann (Kendall) Prentice, was born on March 16, 1782, in Massachusetts. He later changed his last name from Prentice to Prentiss. After his schooling he entered into partnership with a Mr. Bond of Boston, with whom he formed the company Bond and Prentiss, which was in business from 1803 to 1811. On November 6, 1805, he married Sophia Gardner Mellen at Watertown, Massachusetts. They had three children. Bond and Prentiss was a major import company until it was ruined by the embargo of 1807–09, after which Prentiss moved to Lexington, Kentucky. He went into the wool business and soon owned the largest flock of Mexican sheep in the United States. During the War of 1812 he reaped large profits through army contracts, but the peace of Ghent in 1814 broke him financially again.
Along with his brothers John M., Thomas G., and Henry B., Prentiss started his first major land company in Hindostan, Indiana, but the deaths of John and Thomas in November 1820 ended the enterprise. Prentiss returned to New York City to work as a broker and speculator. He was a friend of Samuel Swartwout and kept close contact with Sam Houston. He bought considerable scrip from the Galveston Bay and Texas Land Company, but he was never a partner in the company. In December 1830 he founded the first of two land companies to speculate in Texas, the Union Land Company. For it he had bought scrip covering twenty-eight leagues from the Galveston Bay and Texas Land Company. The second of these ventures, the Trinity Land Company, was founded in January 1834. It was based on scrip for 142 leagues of land, bought from the Galveston Bay and Texas Land Company.
In July 1835 Prentiss claimed to be in possession of nearly all the Texas land scrip on the market and asked the American chargé d'affaires in Mexico, Anthony Butler, to offer the Mexican government $10 million for the cession of nearly all of Texas (with the exception of the Austin, DeWitt, and Robertson grants). In 1849 Prentiss claimed to have invested $1,506,722.08 in his efforts to populate Texas. Although his claims to Texas land were considered invalid by the United States and Mexican governments, he received $122,438 in 1851 for both his land companies. Prentiss died on his estate in Rahway, New Jersey, on September 20, 1857.