The Rhinelander Paper Co. was founded in 1903 and at one time, along with its pulp mill, which closed in the 1970s, employed 1,100 people. The mill has also been owned by St. Regis Paper Co. and by Monarch Paper Corp., which in 1980 sold the mill to Wausau Paper.
In 1908, the Company began making a new white all-sulphite butchers' wrapping, which became known as "King William." The King William butcher wrap proved so popular, the Company abandoned newsprint production in favor of butcher wrap and other dry-finish wrapping papers. In 1913, the Company added a machine that would manufacture tissue paper. In 1916, the Rhinelander Paper Company began producing glassine paper, a nearly transparent, air-tight and grease-proof wrap that had been developed in Germany. Increasing demand for glassine during World War I led to the conversion of a second paper machine for the production of glassine paper (Ticking Off 50 Years, p. 9).
By 1920, the complex of buildings at the Rhinelander Paper Company Paper Mill had expanded to include several machine rooms, two bleaching rooms, two beater rooms, storage and stock rooms, warehouses for sulphur and other resources. The office had moved across the street, to 515 West Davenport Street (1920 Sanborn Map of Rhinelander).
Following World War I, demand for glassine declined. In 1928, the Rhinelander Paper Company's new manager, Folke Becker, undertook a building and modernizing campaign that improved the financial condition of the company, and substantially altered the appearance of the plant. Becker had the paper mill rebuilt in 1928-29, and added a new glassine paper machine and other specialized equipment. As a result of these improvements, the Rhinelander Paper Company became universally regarded as a producer of high quality packaging papers.
Production at the Rhinelander Paper Company continued to expand through the 1950s. Additional glassine paper machines were added in 1937, 1941, 1948 and 1951. In 1953, the Rhinelander Paper Company was said to be "the largest mill in Wisconsin under one roof”. Between 1940 and 1953, the Rhinelander Paper Company production tripled, reaching 50,000 tons, and the number of employees reached 1,250. In 1956, the St. Regis Paper Company purchased the Rhinelander Paper Company. The St. Regis Paper Company expanded the Rhinelander plant substantially in 1966-68. The Monarch Paper Corporation bought the Rhinelander plant in 1978, renaming the plant the Rhinelander Paper Company.
In 1979, Wausau Paper Mills acquired the Rhinelander plant (Oneida County History: 1887-1987, pp. 24-25.).
In 1997, Wausau Paper purchased Mosinee and merged with the Rhinelander Mill.
Oct 11, 2018 Paper mills in Mosinee and Rhinelander have a new owner – Ahlstrom-Munksjo of Helinski, Finland. It said Wednesday that it completed a $615 million deal to buy Expera Specialty Solutions LLC, which also has two mills in northeastern Wisconsin.
In 2013, KPS Capital Partners purchased Thilmany Papers in Kaukauna and the specialty business of Wausau Paper to form Expera Specialty Solutions.