Frederick Ayer (December 8, 1822 - March 14, 1918) was an American businessman and the younger brother of patent medicine tycoon Dr. James Cook Ayer.
In addition to his involvement in the patent medicine business, he is better known for his work in the textile industry.
After buying the Tremont and Suffolk mills in Lowell, Massachusetts, he bought up many textile operations in nearby Lawrence, combining them in 1899 into the American Woolen Company, of which he was the first president.
He was involved in other businesses of the time as well, such as being the co-founder of the Arctic Coal Company .
He died on March 14, 1918, in Thomasville, Georgia, and is interred at Lowell Cemetery.

His home in Lowell is now the Franco American School, a Catholic school, and the Frederick Ayer Mansion on Commonwealth Avenue in Boston, Massachusetts is a National Historic Landmark.

Ayer's first wife was Cornelia Wheaton (1835–1878), daughter of Charles Augustus Wheaton and Ellen Birdseye.
They married on December 15, 1858 and Cornelia's mother died the following day.
The couple had four children: Ellen Wheaton Ayer (1859–1951), James Cook Ayer (1862–1939), Charles Fanning Ayer (1865–1956) and Louise Raynor Ayer (1876–1955).

Daughter Ellen married American Woolen Company's William Madison Wood.

After Cornelia's death, Ayer married Ellen Barrows Banning (1853–1918) in 1884.
They had three children: Beatrice Banning Ayer (1886–1953), Frederick Ayer (1888–1969) and Mary Katherine "Kay" Ayer (1890–1981).

Ayer’s daughter Beatrice married future World War II general George S. Patton.

His nephew, J.C. Ayer's son, was also Frederick Ayer.
Frederick Fanning Ayer, born in 1851, became a lawyer and philanthropist, and was director or stockholder of many corporations.
Frederick Ayer (December 8, 1822 - March 14, 1918) was an American businessman and the younger brother of patent medicine tycoon Dr. James Cook Ayer. In addition to his involvement in the patent medicine business, he is better known for his work in the textile industry. After buying the Tremont and Suffolk mills in Lowell, Massachusetts, he bought up many textile operations in nearby Lawrence, combining them in 1899 into the American Woolen Company, of which he was the first president. He was involved in other businesses of the time as well, such as being the co-founder of the Arctic Coal Company . He died on March 14, 1918, in Thomasville, Georgia, and is interred at Lowell Cemetery.
His home in Lowell is now the Franco American School, a Catholic school, and the Frederick Ayer Mansion on Commonwealth Avenue in Boston, Massachusetts is a National Historic Landmark.
Ayer's first wife was Cornelia Wheaton (1835–1878), daughter of Charles Augustus Wheaton and Ellen Birdseye. They married on December 15, 1858 and Cornelia's mother died the following day. The couple had four children: Ellen Wheaton Ayer (1859–1951), James Cook Ayer (1862–1939), Charles Fanning Ayer (1865–1956) and Louise Raynor Ayer (1876–1955). 
Daughter Ellen married American Woolen Company's William Madison Wood.
After Cornelia's death, Ayer married Ellen Barrows Banning (1853–1918) in 1884. They had three children: Beatrice Banning Ayer (1886–1953), Frederick Ayer (1888–1969) and Mary Katherine "Kay" Ayer (1890–1981).
Ayer’s daughter Beatrice married future World War II general George S. Patton.
His nephew, J.C. Ayer's son, was also Frederick Ayer. Frederick Fanning Ayer, born in 1851, became a lawyer and philanthropist, and was director or stockholder of many corporations.
Frederick Ayer