Born Jason Gould in Roxbury, New York, the future financier received some local schooling. He went to work as a surveyor, then entered the tannery business. During the 1860s, Gould bought stock in small railroads. He later became manager of the Rennsalaer and Saratoga Railway and a guiding force behind the Rutland and Washington Railway.
Jay Gould's reputation as one of the leading robber barons of the era was assured by his actions as a director of the Erie Railroad. In 1869, he worked with allies James Fisk and Daniel Drew to combat Cornelius Vanderbilt's acquisition of the railroad in the infamous Erie War. Gould used every underhanded trick, from bribing public officials to massively watering stock.
Later in 1869, Jay Gould and his partners attempted to corner the gold market, but their scheme fell apart on Black Friday. The public was enraged and thousands of investors were ruined. In 1872, following Fisk's death, Gould was forced out as a director of the Erie.
Over the next few years, Jay Gould focused his attention on the West. Using his extensive wealth, Gould bought his way into control of the Union Pacific and other smaller lines in the Southwest. By the early 1880s, Goulds empire comprised nearly 16,000 miles of track. In 1882, he sold his interest in the Union Pacific. He turned his financial talents toward the Missouri Pacific Railroad, Western Union Telegraph Company, newspapers, and elevated trains in New York City.
Rich, but lonely, Jay Gould worked until the end, diverted only by his books and gardens, and died of tuberculosis.