A trust or corporate trust is a large grouping of business interests with significant market power, which may be embodied as a corporation or as a group of corporations that cooperate with one another in various ways. These ways can include constituting a trade association, owning stock in one another, constituting a corporate group, or combinations thereof. The term trust is often used in a historical sense to refer to monopolies or near-monopolies in the United States during the Second Industrial Revolution in the 19th century and early 20th century. The use of corporate trusts during this period is the historical reason for the name "antitrust law".

In United States history, the Gilded Age is described as the period from about the 1870s to the late 1890s, which occurred between the Reconstruction Era and the Progressive Era. It was named after an 1873 Mark Twain novel by historians in the 1920s who saw this interval of economic expansion as an era of materialistic excesses combined with political corruption.