The Desloge family (//) is one of the oldest French American families in the United States, centered mostly in Missouri and especially at St. Louis. The family rose to wealth through international commerce, sugar refining, oil drilling, fur trading, mineral mining, saw milling, manufacturing, railroads, real estate, and riverboats. The Desloge family are among the “French Aristocrats in the American West”, Carl Eckberg's phrase for the prominent French families in Missouri  whose impact was “characterized as much by family connections, private enterprise and negotiation as by conquest”. The family motto is "Deus Honestum Fortis" (God, Honor, Strength).
The family has funded hospitals and donated large tracts of land for public parks and conservation.
The family's progenitor was Firmin René Desloge, a descendant of French nobility who emigrated to Missouri in 1823 to join his uncle Jean Ferdinand Rozier who had arrived in Missouri in 1810 with Rozier's business partner John James Audubon.
The family's businesses in lead and mercantile in Missouri date from around 1824, when Firmin Rene Desloge built his own smelting furnace as an extension of his Potosi, Missouri, mercantile business. They grew to include the Missouri Lead Mining and Smelting Company in 1874 and the Desloge Lead Company in 1876, inclusively one of the largest and oldest lead mining companies in America.
The family moved to St. Louis in 1861, at the outset of the American Civil War, after various attacks at Potosi, Bonne Terre and upon the family lead mining works by both Federal and Confederate armies who sought lead for weapons.
Firmin Rene Desloge's son, Firmin V. Desloge, expanded mining operations and expanded management to Bonne Terre, Missouri; a charter was requested and granted to the Missouri Lead and Smelting Company on June 5, 1874. The corporate name was later changed to “The Desloge Lead Company” on February 21, 1876. Three shafts were sunk during 1876 and 1877 and a new mill was built. In 1886, a fire destroyed the concentrating mill plant and damaged the rest of surface plant of the Desloge Lead Company. Rather than rebuild, Desloge sold the firm to the St. Joseph Lead Company. In 1887, the land was cleared and company houses for his staff were constructed at the location which became known as Deslogetown, present day Desloge, Missouri. Desloge then founded a new company, the Desloge Consolidated Lead Company.
To serve his mines, Firmin Desloge also built the first railroads to penetrate the disseminated lead field of St. Francois County, Missouri: the Desloge Railway, the Mississippi River and Bonne Terre Railway and then the Valley Railroad. Firmin Desloge II was also involved with the development of the Iron Mountain and Southern Railroad (aka the Iron Mountain Railroad) from St. Louis, Missouri, to Texarkana, Arkansas. The St. Joseph Lead Company built a 13.5-mile narrow gauge railroad from the mines to a junction with the Iron Mountain Railroad at Summit in Washington County. St. Joe paid two-thirds of the construction costs; the Desloge Company the rest.
Around 1916, the Desloge Consolidated Lead Company moved its corporate offices from Desloge, Missouri, to the Rialto Building in downtown St. Louis. While "St. Louis, with its French ancestry, has been noted as a fur capital, more money passed through St. Louis as a result of the lead business in Missouri than did because of the fur business,” wrote Doe Run Company CEO Jeffry Zelm. The oldest St. Louis-based lead family is Desloge.
Desloge's new company operated until 1929, when it was sold to the St. Joe Lead Company for $18,000,000 (about $360 million in 2011 dollars). “With the absorption of the Desloge concern by the St. Joseph Lead Company, one of the oldest mining companies of the district goes out of existence as a company." The sale made the family worth more than $52 million alongside W. K. Vanderbilt ($52 million) and A. W. Mellon ($50 million), but only half as wealthy as the Astors ($100 million)
In 1922, Firmin's grandson Louis Desloge (from Jules Desloge) founded Watlow — the name alludes to low-watt heaters to replace steam heat — to manufacture electric heating elements for the shoe industry. In 2011, Watlow, still a Desloge family business, employed 2,000 employees in 13 factories in the United States, Mexico, Europe and Asia; had sales offices in 16 countries; and distributed globally.
Firmin Desloge, II son, Joseph Desloge, designed an industry-specialty electric fuse that would "kill the arc" and founded Killark Electric in 1913. Joseph Desloge also owned Minerva Oil, (a confusing misnomer as it was primarily mining zinc and fluorspar); and founded Louisiana Manufacturing Company and Atlas Manufacturing Company; and fluorspar mining in southeastern Illinois. Joseph Desloge’s son Joseph Jr. owned uranium mines near Moab, Utah, which he and his partner sold to General Electric; he also made money in natural gas exploration in Lycoming County, Pennsylvania.
The Desloge family entertained Russian ballerinas and Shakespearean actors, King Hussein of Jordan, the archduke of Austria (giving him brief shelter after he was deposed by the Nazis), and Anne Morrow Lindbergh.
Firmin Desloge, II died in 1929 as one of the wealthiest men in the world.
Louis Fusz married Firmin Desloge’s daughter Josephine, and the Fusz family played several key roles in the ownership and management of the Desloge Consolidated Lead Company. Louis Fusz was president of Regina Flour Mill Co., and of Desloge Consolidated Lead Co. The Fusz name in St. Louis today is automobiles. In 2011, after 58 years, the Lou Fusz Automotive Network consists of 16 car dealerships.
Theodore (Ted) Desloge Jr was a founding partner in and president of Park 'N Fly, established in 1967 as the first and today the nation's leading off-airport parking company Ted has also been director of Valley Forge Corp. and Mississippi Valley Bankshares, Inc.; and founder of Janna Medical Systems.
Christopher D. Desloge (born July 23, 1958) is founder and trustee for Madaket Growth — until 2004, Desloge Consolidated Lead Company— a St. Louis-and-New York-based private family investment holding company;
Three Desloges — Diane Waring Desloge (daughter of William L. Desloge), Anne Kennett Farrar Desloge (daughter of Joseph Desloge, Sr.) and Katherine Falk Desloge (daughter of Stephen F. Desloge) — have been "Queen of Love and Beauty" at the Veiled Prophet Ball, a debutante ball held in December in St. Louis.
Durie Malcolm, wife of Firmin V Desloge, III, was in 1947 allegedly briefly married to John F. Kennedy in Palm Springs, Florida. This long-rumored story was verified in 1998 by Malcolm's sister-in-law, Mrs. William L. Desloge, who said, "Of course it's true, we were all there at the parties in Palm Beach with them."
The 1932 bequest of Firmin V. Desloge funded the Firmin Desloge Hospital, today known as St. Louis University Hospital; a separate bequest one year later from his wife, Lydia Desloge, built a Desloge Chapel at the hospital. Firmin V. Desloge willed his original 47 acres of his hand-dug pits of the original lead mining operations and the deeply rutted wagon tracks on a property in Washington County. The family then donated this land for a park, today named Firmin Desloge Park, and dedicated it to the mining families in the area.
In 1955, Joseph Desloge donated to the state of Missouri some 2,400 acres of land acquired over 17 years in Reynolds County. The land, which included a shut-in region and more than two miles of river frontage, today composes the bulk of Johnson's Shut-Ins State Park. He continued donating money to improve the park. Desloge also donated land for Sunset Park in north St. Louis County on the Missouri River; and sold to St. Louis County - for next to nothing ($91 an acre) - the 2,300-acre Pelican Island in the middle of the Missouri River as a nature preserve.
In 2006, Theodore P. Desloge, Jr., great-grandson of Firmin V. Desloge, and his wife donated $5 million for the Mr. and Mrs. Theodore P. Desloge, Jr. Outpatient Center of St. Lukes Hospital in St. Louis.
In 2013, Christopher D. Desloge founded the Foundation for Commercial Philanthropy, a Missouri and Connecticut nonprofit social entrepreneurial holding company intended to serve the poor and homeless by raising funds through various commercial businesses. Mr. Desloge also is in lay ministry as a Franciscan (Society of St. Francis Associate and Third Order Novitiate) 
- The article is the condensed version of 900-page historical monograph supported by materials at historical societies, over 230 bibliographic sources under ISBN, with copyright and Library of Congress application
- Stevens, Walter B. St. Louis The Fourth City 1764–1911. 2 vols. St. Louis-Chicago: S. J. Clarke Publishing Co., 1909 and 1911.
- "A French Aristocrat in the American West: The Shattered Dreams of De Lassus De Luzières", Carl J. Ekberg, University of Missouri; 1st Edition (Dec 27 2010)
- Attribution of this coined phrase of Carl Ekberg to the Desloge family located in the written permission by Carl J Ekberg, on file at the Missouri History Museum, Research and Reference Building, St. Louis, MO
- Jay Gitlin, The Bourgeois Frontier: French Towns, French Traders & American Expansion
- The Desloge Family in America
- History of Southeast Missouri. Robert Sidney Douglass, Lewis Publishing Company, Chicago and New York, 1912
- “Descendance de Joseph-Gilles Desloge.” 2 pp. typewritten, n.d. Translated by Rosemary T. Power. Missouri Historical Society Archives, Joseph Desloge Collection
- Huger, Lucie Furstenberg. The Desloge Family in America. St. Louis: Nordman Printing Co., 1959
- Sharpe, Mary Rozier and James, Louis, Between the Gabouri, History of the Rozier Family, 1981
- Arthur, Stanley Clisy. Audubon: An Intimate Life of the American Woodsman, 1937
- Desloge Consolidated Lead Company records at Missouri Historical Society, St. Louis, MO
- Thomas A. Rickards. A History of American Mining, Maple Press Co., New York, 1937
- Bouchard, W. L., A Trip Through Bonne Terre Mines and Surface Operations, published by The Lead Belt News, Flat River, St. Francois Co. MO, Fri. March 4, 1949.
- HISTORY OF THE LEAD BELT OF ST. FRANCOIS COUNTY MISSOURI By A. J. Norwine (1924)
- History of St. Joe Lead Company http://www.rootsweb.ancestry.com/~mostfran/mine_history/stjoe_history.htm
- Sullivan, John J., History of St. Joe and Desloge Railway and Missouri River and Bonne Terre Railroad, handwritten, Railroads Collection, Desloge Railway, Missouri Historical Society archives
- Missouri Short Line Railroad
- McHenry, Robert E. "Chat Dumps of The Missouri Lead Belt".
- "The History of the Desloge Family in America", by Christopher Desloge, lulu.com (2013). Yale University professor and Director of French American history on the American Frontier Jay Gitlin (Faculty: Environmental History at Yale) called "The History of the Desloge Family in America" “one of the most serious and major contributions on the subject…a foundation of work for thousands of academics and historians”, in his foreword to 2012 "Desloge Chronicles". Missouri History Museum, Research and Reference Building, St. Louis, Missouri.
- May 31, 1929 The Lead Belt News
- McHenry, Robert E. Chat Dumps of The Missouri Lead Belt, St Francois County. With an Illustrated History of the Lead Companies that Built Them, Flat River, Bonne Terre, Desloge, River Mines, Leadwood, Elvins, Leadington, self-published, 2006.
- Thompson, Henry C. Our Lead Belt Heritage. Flat River, Mo., 1955
- Probated will of Lydia Desloge, source Farmington (Missouri) Press, December 1932
- List of the Richest Men in the World, New York Times, May 20, 1923, accessed by ProQuest Historical Newspapers, via St. Louis County Library.
- Joseph Desloge Jr., Passport To Manhood, 1995, p102
- St. Louis Magazine, article "The Desloge Family: Getting the Lead Out" By Jeannette Cooperman August 20, 2015, http://www.stlmag.com/news/the-desloge-family/
- Missouri Historical Society, William L. Desloge, President
- List of the Richest Men in the World, New York Times, May 20, 1923, accessed by ProQuest Historical Newspapers, via St. Louis County Library.
- oldest 1967
- Park ‘N Fly has been operating for nearly 50 years in 14 markets, with 16 facilities, and 80 affiliate locations compared to the second largest Parking Company of America has only 13. https://www.nytimes.com/fodors/top/features/travel/destinations/unitedstates/georgia/atlanta/fdrs_feat_15_7.html?n=Top%2FFeatures%2FTravel%2FDestinations%2FUnited+States%2FGeorgia%2FAtlanta
- "History". Madaket Growth. Retrieved 12 July 2013.
- "Madaket Growth, LLC". SOS Home :: Business Services :: Business Entity Search. Missouri Secretary of State. Retrieved 12 July 2013.
- "Rick Desloge - St. Louis Business Journal". bizjournals.com. Retrieved 2 August 2015.
- Dark Side of Cemelot, Seymour Hersh, Little Brown, 1998
- The Smoking Gun http://www.thesmokinggun.com/file/tale-jacks-first-wife
- The Daily Mail, July 20, 2015, http://www.dailymail.co.uk/news/article-3154984/Was-JFK-bigamist-eve-Jackie-Kennedy-s-86th-birthday-mystery-president-married-Palm-Beach-socialite-lingers.html
- History of the Desloge Family in America, Christopher D Desloge, p. 212, lulu press, 2013, accessed at the Missouri History Museum, 2017
- "The Southeast Missourian - Google News Archive Search". news.google.com. Retrieved 2 August 2015.
- Missouri History Museum, fully executed bequest documents in the possession of the Missouri Historical Society Archives, St. Louis, MO, Joseph Desloge Collection, http://www.mohistory.org/files/archives_guides/Guide_to_the_Archival_Collections_A-Z.pdf (Item A0380)"legal contracts concerning the building and endowment of the Firmin Desloge Hospital"
- Christopher Desloge, Desloge Chronicles, lulu, 2010 pp 757
- Missouri History Museum, http://collections.mohistory.org/resourceMgr/103225.html
- "Johnson Shutins, Auctioneers, and Joe Desloge. - St. Louis Auctions, St. Louis AuctioneerAuction St. Louis". auctionstlouis.com. Retrieved 2 August 2015.
- Joseph Desloge, Jr. Passport To Manhood, 1995, p.18 & 103
- Christopher Desloge, Desloge Chronicles - Tale of Two Continents, lulu, 2010, pp 758
- Christopher Desloge, Desloge Chronicles, lulu, 2010, pp 759
- Private deed transfer papers in the possession of Loriel Desloge Hogan
- Article. Center site
- Desloge, Christopher (September 3, 2013). "Foundation for Commercial Philanthropy Organized to Raise Funds for the Poor, and aid NPOs". Press Release. The Foundation for Commercial Philanthropy, Inc. Retrieved June 13, 2016.
- Southeast Missouri Mining and Milling. Doe Run Company. 2004
- Potosi (Missouri) Historical Society
- "History of the Lead Belt". rootsweb.ancestry.com. Retrieved 2 August 2015.
- "St. Joe Lead Company to Absorb Desloge Lead Co.". rootsweb.ancestry.com. Retrieved 2 August 2015.
- "Desloge Family". carrollscorner.net. Retrieved 2 August 2015.
- "Saint Louis University Timeline". slu.edu. Retrieved 2 August 2015.
St. Louis Magazine, The Desloge Family, Aug, 20, 2015 http://www.stlmag.com/news/the-desloge-family/