|United States Ambassador to Belgium|
|Preceded by||Nicolas Fish|
|Succeeded by||John G. Parkhurst|
|United States Ambassador to Russia|
|Preceded by||George V. N. Lothrop|
|Succeeded by||Allen Thorndike Rice|
Lambert Tree (November 29, 1832 – October 9, 1910) was a United States state court judge, ambassador, and patron of the arts.
Born in Washington, D.C., Tree went to the University of Virginia. He studied law, was admitted to the Virginia bar, and then moved to Chicago, Illinois. He practiced law and, in 1870, was elected to the Cook County, Illinois circuit court. Tree presided over the indictment, trial, and conviction of corrupt City Council members. He lost the 1882 United States Senate race by one vote, then fell seven votes shy in 1885. However, later in 1885, he accepted an appointment from President Grover Cleveland as minister to Belgium. He then served the shortest tour, less than one month, of all U.S. Ministers to Russia: after his presentation of credentials on January 4, 1889, he left post on February 2, 1889, not long before the inauguration of President Cleveland's successor, Benjamin Harrison, a Republican.
Tree was married to Anna Josephine Magie in 1859; the couple had a son, Arthur, who married Ethel Field, the daughter of American millionaire Marshall Field in a lavish ceremony at the Field's mansion on Prairie Avenue.
While travelling back from a European trip on a steamboat in early October 1903, his wife died. Seven years later, on 9 October 1910, Tree died in the Waldorf Astoria New York from heart failure. When Tree died he had been returning from visiting his son at his home on his country estate in England; Tree had never been happy that Arthur decided to live abroad and demonstrated his displeasure with the situation by stipulating in his will that his grandson, Ronald Tree, should receive his education in America.
Tree Studio Building
A patron of the arts, Judge Tree and his wife had an artists studio constructed in 1894 at 603-621 N. State St., to provide low cost housing and space for artists. The Tree Studio Building is important architecturally for its picturesque details of the period. After its original construction, two wings (located on Ohio and Ontario) were added during 1912–1913, forming a distinctive courtyard. This U-shaped complex is now closed off at the other end by the Medinah Temple. Tree Studios is one of the nation's oldest such studios, the original portion being designated a Chicago landmark February 26, 1997.
Lambert Tree Award
In 1887, Judge Lambert Tree and Chicago Mayor Carter H. Harrison put up the funding for civilian awards given annually to an individual member of the Police and Fire Departments who demonstrate outstanding bravery in the line of duty. Currently, the medal presentations are rotated from year to year, so neither award is perceived as better than the other. The awards are given out during Fire Prevention Week in October each year for the preceding twelve months. In 1999, the Fire Department designee received the Lambert Tree Award, thus in October, 2000, the department recipient will receive the Carter H. Harrison Award. These awards have been presented annually (with the exception of the years 1890–1896) since March 4, 1887. (dead link). A listing of police award recipients by year, with a little description can be found online. 
- "Inventory of the Lambert Tree papers, 1821-1933". Newberry Library. Retrieved 21 March 2015.
- "Marriage of Miss Field", Chicago Tribune, p. 3, 2 January 1891 – via Newspapers.com
- "Mrs Lambert tree dead", St Louis Republic, p. 36 – via Newspapers.com
- "Lambert Tree dead", Pittsburgh Post Gazette, p. 2 – via Newspapers.com
- "Arthur M. Tree is Dead in his Home in England", Chicago Tribune, p. 1, 28 September 1914 – via Newspapers.com
- "Tree Studios and Medinah Temple - World Monuments Fund". Retrieved 26 February 2017.
- Lambert Tree Award Archived 2016-03-03 at the Wayback Machine
- ChicagoCop.com. "ChicagoCop.com - Carter H. Harrison / Lambert Tree Award Recipients". Retrieved 26 February 2017.
Nicholas Fish II
| United States Minister to Belgium
John G. Parkhurst
George V. N. Lothrop
| United States Minister to Russia
September 25, 1888 – February 2, 1889
Allen Thorndike Rice