- Born Michael Strauss Jacobs March 17, 1880, at 17 Washington Street, New York City
- Parents: Isaac Jacobs & Rachel Strauss, both immigrants
- Siblings: 2 brothers & 7 sisters
- Married French-Canadian Josie Pelo
- His early business ventures included buying the concession rights for boats traveling in the New York Harbor area, and a ticket agency at the Hotel Normandie at Broadway and 39th Street, across from the Metropolitan Opera House, becoming the "standout ticket agent of New York."
- Got his start in boxing "scalping" Terry McGovern tickets in 1900 by buying tickets directly from patrons exiting the ticket office and re-selling them right before each bout at inflated prices.
- Former advisor and "money man" for Promoter Tex Rickard from the time of the 1919 Jack Dempsey-Jess_Willard bout. They first met at Goldfield, Nevada, in 1906 when Rickard promoted the Joe Gans-Battling Nelson bout.
- Long-time promoter for Madison Square Garden (he staged 320 shows there from 1937-1949) and the St. Nicholas Arena. Before then, he had staged shows at the old Hippodrome on Sixth Avenue.
- Jacobs's promotional company was the Twentieth Century Sporting Club. The last show he promoted ,at Madison Square Garden under the Twentieth Century Sporting Club banner, was May 20, 1949.
- During his heyday from the late 1930s to the late-1940s, until declining health and the retirement of Joe Louis in 1949 ended his run, Jacobs was arguably the most powerful man in boxing. Jacobs controlled every world title between Featherweight and Heavyweight, with some resistance, most notably at Middleweight. During this time, most title bouts were fought at Madison Square Garden, or at other New York City venues under his direction.
- Suffered a cerebral hemorrhage in December 1946
- Promotional Record (incomplete)
- Inducted into the World Boxing Hall of Fame, "Expanded Category" (Promoters & Matchmakers)
Source for much of the above: The Mike Jacobs Story (1950)