Brunswick Corporation, formerly known as the Brunswick-Balke-Collender Company, is an American corporation that has been developing, manufacturing and marketing a wide variety of products since 1845. Brunswick has more than 13,000 employees in 24 countries. Brunswick owns a number of brands, including Mercury Marine. In 2024, Brunswick reported sales of US$5.2 billion. Brunswick's global headquarters is in the northern Chicago suburb of Mettawa, Illinois.

Brunswick was founded by J. M. Brunswick who came to the United States from Switzerland at the age of 15. The J. M. Brunswick Manufacturing Company opened for business on September 15, 1845, in Cincinnati, Ohio. Originally J. M. Brunswick intended his company to be mainly in the business of making carriages, but soon after opening his machine shop, he became fascinated with billiards and decided that making billiard tables would be more lucrative, as the better tables then in use in the United States were imported from England. Brunswick billiard tables were a commercial success, and the business expanded and opened the first of what would become many branch offices in Chicago in 1848. It was later renamed J. M. Brunswick & Brother by 1860, after a family member came on board, and the company's slogan at this time was: "The oldest and most extensive billiard table manufacturers in the United States".

In 1874, the Brunswick company merged with competitor Great Western Billiard Manufactory owned by Julius Balke to become the J. M. Brunswick & Balke Company. It was incorporated in 1879 with a capital stock of $275,000, the same year it merged with another competitor, H. W. Collender Company of New York City (founded by Hugh W. Collender), to acquire Collender's patented billiard cushions. In 1884, the partners formed the Brunswick-Balke-Collender Company (or B.B.C. Company for short) with capital of $1.5 million.^{[clarification needed]}

The company expanded into making a number of other products. Large ornate neo-classical style bars for saloons were a popular product. Bowling balls, pins, and equipment led a growing line of sporting equipment. It popularized bowling balls of manufactured materials, vulcanized rubber at first; earlier bowling balls had been solid wood.

In the early 20th century, Brunswick expanded the product line to include such diverse products as toilet seats, automobile tires, and phonographs. In the late 1910s, they introduced a quickly popular line of disc phonograph records, under the name Brunswick Records. In 1930, Brunswick sold the control of the record company to Warner Brothers and came out with a line of refrigerators.

During World War II, Brunswick-Balke-Collender made small target-drone aircraft for the U.S. military. After the war, Brunswick introduced a line of school furniture. In 1949, the Brunswick "Model A" Mechanical Pinsetter fully automated unit premiered, for the purpose of handling bowling pins for ten-pin bowling, in competition with American Machine and Foundry (AMF). Previously, Brunswick had made two models of semi-automated, manually operated "spotting tables" for the tenpin sport, that the "Model A" unit replaced.

A historical marker at 623 S. Wabash Ave. in Chicago was dedicated by the Illinois State Historical Society in 1995 at the site of Brunswick's headquarters from 1913 to 1964. The building today is used by Columbia College Chicago.

The 1950s also saw the introduction of a line of golfing equipment to compete with AMF in the leisure-products and sporting-goods markets.