On October 15, 1914, Congress passed the Clayton Antitrust Act to clarify and supplement the Sherman Antitrust Act of 1890.

The Clayton Act outlawed trusts formed by two companies with interlinking boards of directors, price-fixing with businesses offering competing products, making agreements with other businesses to control the supply of a product, and abusing power to gain or maintain a monopoly.

On October 15, 1582, the Gregorian Calendar was implemented, following a papal bull issued by Pope Gregory XIII. Spain, Portugal, Poland, and Italy were the only nations to adopt the calendar on this day, but it spread over the succeeding centuries to become the international standard today. Learn more about the history of the Gregorian calendar.