Carter Henry Harrison III (February 15, 1825 – October 28, 1893) was an American politician who served as mayor of Chicago, Illinois, from 1879 until 1887 and from 1893 until his assassination.

[3][5] Harrison's family had a long Southern lineage, dating back to early colonial Virginia.

[12] Harrison had been the leading figure in the formation of the Union–Fireproof Ticket[2] and served as the chair of its nominating convention.

[2] Early into his tenure on the county board, Harrison ran an unsuccessful campaign in 1872 as the Democratic nominee in Illinois's 2nd congressional district for election to the 43rd United States Congress.

Harrison, while unsuccessful, managed to greatly outperform previous Democratic nominees in the district.

[17] The Chicago Tribune would blame local Republicans' alignment with the Citizens Union ticket in the 1873 local Chicago elections as detrimental to Ward's re-election, as in the eyes of many voters it had placed Republicans on the less popular side of the "beer question" (positioning them in support of enforcing Sunday temperance blue laws (laws banning the sale of alcohol on Sundays).

Many voters who typically voted Republican had in 1873 voted for the People's Party instead of the Citizens Union ticket due to the "beer question"[17] At the time he was elected, he had been out-of-country visiting Europe with his family (traveling to Austria, Germany, Switzerland, and the Tyrol).

[20] Scandal occurred in his second term in congress when, as chairman of the Committee on Reform of the Civil Service, Harrison had pushed through the payment of benefits to four self-proclaimed Union Army veterans purporting disabilities from wartime injuries despite the fact that their claims had previously been rejected.

[22] During his first mayoralty, he surpassed his predecessor Monroe Heath's title as the longest serving mayor Chicago had had up to that time.

[2] Harrison would later remark that, when he took office as mayor, "there were not ten miles of paved street in the whole city over which a light vehicle could move rapidly without injury to wheel or axle.”[2] Long a booster of his adopted city, Harrison was known to refer to Chicago as his "bride".

[10] Harrison also forced utility companies operating in the central business district to bury their wires.

He also worked to persuade railroads to begin elevating their tracks to eliminate level crossings.

[10] Harrison's first mayoral tenure was a period that saw many events which brought the city national and international attention.

Early on the evening of the Haymarket affair in 1886, Harrison had casually observed the then still peaceful demonstration of anarchists and trade unionists and advised the police to leave the demonstrators alone; he then left the scene before the riot and anarchist bomb-throwing occurred.

A significant reason for his ability to attend the rally unbothered was that, while Harrison came from a Protestant background, he needed the votes of and thus made appeals to the city's large ethnic White Catholic population as well as its rapidly growing numbers of trade unionists.

His administration gave the impression of being more favorable to trade unions and strikes than those of previous Chicago mayors as well as other mayors of the time, although his police force routinely put down striking workers and trade union activists when they interfered with the businesses hiring replacements.

[26][10] Harrison's handling of the Haymarket Riot had also harmed his standing with conservative business groups.

[26][10] Recognizing that he would have difficulty being re-nominated by the Democratic Party, Harrison decided to retire at the end of his fourth term, opting against seeking re-election in 1887.

Experiencing great grief over his wife's passing, he withdrew from the election,[4] and instead embark on international travels.

[30] On July 26, 1887 Harrison embarked on international travels,ref name="TopekaDailyPress1"/> taking a sixteen-month world tour.

[4] In 1890, Harrison and his daughter took a vacation trip from Chicago to Yellowstone National Park and Alaska.

His letters from the trip were first published in the Chicago Tribune and later compiled into an 1891 book, A Summer's Outing and The Old Man's Story.

[7] THis marked a return to political engagement, as he used this newspaper to advocate for labor unions and the many Catholic and immigrant communities in Chicago.

[citation needed] Harrison unsuccessfully sought to stage a comeback, running in the 1891 Chicago mayoral election.

[32] Harrison's first acts after being sworn-in were to immediately submit vetoes of several ordinances that the council had already passed, one which served the interests of the Midland Elevated Railway (which stockbroker James R. Keene held significant stake in) and another which would have granted the Hygeia Springs Company permission to supply water into the city.

[33] Harrison appointed 1st Ward Alderman "Bathhouse" John Coughlin to sit on the reception committee for the world's fair.

[36] A celebration planned for the close of the Exposition was cancelled and replaced by a large public memorial service for Harrison.

While Harrison died at a time when the elites, Protestants, and Republicans of all kinds greatly disliked him, he never lost his core supporters of labor unions, Catholics and immigrants.

Harrison's career and assassination are closely associated with the World's Columbian Exposition, and are discussed at some length as a subplot to the two main stories (about the fair and serial killer H. H. Holmes) in Erik Larson's best-selling 2003 non-fiction book The Devil in the White City.

[37] After being widowed, Harrison married Margarette (alternatively spelled "Margaret" or "Marguerite") E. Stearns in 1882.