US History STAAR End-of-Course (EOC) Practice Test

Horizontal integration is when a company gains control over other firms that produce the same kind of product, reducing competition and increasing market power. John D. Rockefeller built Standard Oil by buying rival refineries and forming trusts that brought many independent oil producers under one umbrella, creating a dominant monopoly in oil refining. This is the classic example of horizontal integration. Andrew Carnegie pursued vertical integration by controlling the steel production process from raw materials to finished product. Henry Ford is best known for mass production and the assembly line, not horizontal expansion through acquiring competitors. J. P. Morgan was a financier who organized large mergers, but the landmark example of horizontal integration in oil is Rockefeller’s Standard Oil.