The Liverpool and Great Western Steamship Company, known commonly as the Guion Line, was a British passenger service that operated the Liverpool-Queenstown-New York route from 1866 to 1894. While incorporated in Great Britain, 52% of the company's capital was from the American firm, Williams and Guion of New York. Known primarily for transporting immigrants, in 1879 the line started commissioning Blue Riband record breakers to compete against Cunard, White Star and Inman for first class passengers. The financial troubles of one of the company's major partners in 1884 forced the firm to return its latest record breaker, the Oregon, to her builders and focus again on the immigrant trade. The company suspended sailings in 1894 because of new American restrictions on immigrant traffic.
In 1848, John Stanton Williams (c. 1810-1876) and Stephen Barker Guion (1820-1885) formed the New York firm of Williams and Guion to operate the Black Star Line of sailing packets on the Liverpool-Queenstown-New York route. In 1852, Guion relocated to Liverpool as the firm's agent while Williams remained in New York. The next year, Guion's older brother, William H. Guion joined the firm's New York office. The Black Star Line concentrated on the steerage trade and ultimately owned 18 sailing ships. Black Star was shut down in 1863 because of the success of iron-screw liners in attracting steerage passengers and the danger of Confederate commerce raiders during the Civil War. Stephen Guion, by now a naturalized British citizen, contracted with the Cunard Line and the National Line to provide steerage passengers.
In 1866, Stephen Guion incorporated the Liverpool and Great Western Steamship Company in Great Britain to operate a quartet of 2,900 GRT liners for a weekly service to New York. Although 52% of the capital came from the Williams and Guion partnership, the Guion Line was formed as a British company because American law only allowed U.S.-built ships to be registered in the U.S., and American shipyards were incapable at that time of building the iron-hulled screw steamers required to compete on this route. Guion took advantage of an 1846 legal decision that considered a British corporation as a British citizen even if its shareholders were largely foreigners.