American manufacturer and marketer of foods and beverages, formed in August 2001 when PepsiCo, Inc., acquired the original Quaker Oats Company of Chicago, Illinois. The company operates as a division within PepsiCo.

The Quaker Oats trademark was registered in 1877 by Henry Parsons Crowell (1855–1944), an Ohio milling company owner who in 1891 joined with two other millers, Robert Stuart and Ferdinand Schumacher, in creating the American Cereal Company. By the late 1890s a management conflict had broken out between the three men. At first, Schumacher forced out Stuart and Crowell, but they returned in a share and proxy war, ejected Schumacher, and in 1901 converted American Cereal into the Quaker Oats Company. By this time Quaker was producing oat and wheat cereals, hominy, corn meal, baby food, and animal feed. Crowell, president until 1922, was succeeded by Stuart's son John, who presided for 34 years, working with his younger brother R. Douglas Stuart, a promotional genius.

By the late 20th century, hundreds of food products had been added (e.g., Cap'n Crunch breakfast cereal and Aunt Jemima syrup, mixes, and frozen waffles and pancakes). Following the corporate trend of the 1960s and '70s, the company diversified into chemical products, restaurant chains, and the toy industry. Most of these assets were sold by the early 1990s, however, as Quaker refocused on its food products, which came to include Rice-a-Roni, Quaker snack products, and breakfast cereals. It moved into the beverage market by adding Gatorade sport drink in 1983 and acquiring Snapple, a bottler of iced teas and fruit drinks, in 1994. Although lagging sales caused Quaker to sell the Snapple business in 1997, the company continued to expand the Gatorade brand by introducing nutritional drinks and snacks.