Henderson was born in Seneca Falls, New York, the daughter of Eunice Newton and Elisha Foote, a prominent lawyer and judge, and the niece of Senator Samuel Foote of Connecticut, whose proposed land law caused the historic 1830 debate between Daniel Webster of Massachusetts and Robert Hayne of South Carolina. Henderson was educated at Temple Grove Seminary, Saratoga Springs, and at Ashgrove Seminary, in Albany, finishing at a French school in New York City. She was fluent in French and had a life-long interest in painting and art collecting. In June of 1868 she was married to John B. Henderson, Senator from Missouri (1862-1869) who is known as one of the authors of the Thirteenth Amendment, and one of seven Republicans who voted against the impeachment of President Andrew Johnson in May 1868. That unpopular decision ended his career as senator, and he and his new wife moved back to Missouri, living first in the town of Louisiana and then in St. Louis, where John Henderson established a successful law practice, ran for governor in 1872 (but lost), served as a special United States Attorney, and was chairman of the 1884 Republican National Convention in Chicago. The couple had one child, John Henderson Jr., who was born in 1870.
Mary Henderson pursued many interests in St. Louis. Like her mother before her, she believed in woman's suffrage, and became president of the Missouri State Suffrage Association. She studied art at Washington University, and founded the St. Louis School of Design, an industrial arts school, as well as the St. Louis Women's Exchange. Known as an excellent hostess, she wrote a guide to fine entertaining, Practical Cooking and Dinner Giving, in 1877. She writes in the Preface, "No claim is laid to originality." Rather, Henderson used her experience and her knowledge of cooking, as transmitted from teachers in America and Europe, to pick and choose the best recipes for her collection. Her elaborate instructions on setting the table, how to send and receive invitations, and how dinner should be served, as well as her choice of recipes and menus, reveal how the upper class conducted the rituals of meals and entertaining in nineteenth century America. (In fact, when Edith Wharton's The Age of Innocence was turned into a Martin Scorsese film, the film stylist used Practical Cooking and Dinner Giving as a historical guide.) The book went through several editions, and was popular into the 1920's. In 1885, Henderson published a second cookbook, Diet for the Sick, A Treatise on the Values of Foods, their Application to Special Conditions of Health and Disease, and on the Best Methods of their Preparation.
The Hendersons became very wealthy when John Henderson bought up enormous quantities of supposedly worthless bonds that Missouri counties had issued after the war. Purchased at ten cents on the dollar, the bonds became valuable when the courts ordered counties to pay Henderson their full face value. In 1889, after accumulating a fortune, the Hendersons moved back to Washington D.C., where they built a castle-like mansion on Sixteenth Street called "Boundary Castle." Henderson had the large area of land surrounding her mansion designed into a beautiful, residential area. She erected mansions to the specifications of foreign diplomats, and rented the stunning homes of Sixteenth Street to the embassies of France, Italy, Spain, Cuba, Mexico and Poland. The "doyenne of the diplomatic clique," and the hostess to Presidents, Senators and cabinet members, Henderson was the leading Washington socialite of her time. In 1898, she asked Paul Pelz, co-architect of the Library of Congress, to design a new presidential mansion to be located on Meridian Hill property owned by the couple. Though Henderson petitioned Congress to accept the generous offer of a new White House - a castle designed by Pelz - Congress declined. Later in her life, Henderson would again offer a generous gift of a residence, a $500,000 mansion she intended for the Vice-President's residence. Calvin Coolidge, vice president at the time, toured the home, but the government thought it would be too costly for the Vice President to maintain such a grand house.
Henderson became a strong advocate for temperance and vegetarianism, and published a book on health and diet called The Aristocracy of Health. A Study of Physical Culture, Our Favorite Poisons, and a National and International League for the Advancement of Physical Culture (1904). When her husband passed away in 1913, she had his entire wine cellar, a thirty-year collection of costly wines, emptied into the street. In a 1916 interview, she explained, "When every person is careful that food and drink makes for good and not for evil results for the body, it is a long stride toward taking care of the soul." Henderson died at Bar Harbor, Maine in 1931. Her estate was estimated to be worth between five and six million dollars.
Many thanks to the Missouri Historical Society for providing the following sources:Encyclopedia of the History of St. Louis. Vol. II. William Hyde and Howard L. Conard, Eds. St. Louis: The Southern History Company, 1899.
"Film Fest," Washington Post Magazine, January 1994.
"Gourmet or Gourmand" from "The Director's Notebook," Missouri Historical Society Bulletin. October, 1966, pp. 76-77.
"Meridian Hill: What Might Have Been," Washington Post (Style Section), February 1999.
"Mrs. Henderson Offers U.S. $500,000 Mansion," St. Louis Globe Democrat, January 26, 1923.
"Washington's Social Queen," St. Louis Globe Democrat, July (day unknown), 1931.
"Widow of a Famous Missouri Senator Wishes Uncle Sam To Accept Her 'White House' for Senate Presidents in Memory of Her Husband and Son," St. Louis Post-Dispatch, February 11, 1923.
"Widow of Former Missouri Senator Responsible for Making National Capital a More Presentable City," St. Louis Globe Democrat, March 5, 1916.
"Widow of Missouri Senator Rules Washington Diplomatic Society and Sells Her Houses," St. Louis-Post Dispatch, April 26, 1925.
Untitled article on Henderson family and estate, St. Louis Post-Dispatch, February 22, 1931.