While the United States presidency had long had no formal term limits, it was generally respected that no president would serve longer than the two terms served by the first president, George Washington. Ulysses S. Grant was elected president in 1868 and re-elected in 1872; there was speculation that he would run for a third term in 1876.
 
The term “Caesarism” (meaning “emperor” or “dictator”) had been used earlier in the 19th century, but it became the favored term for describing Grant’s proposed third term. Harper’s Weekly cartoonist Thomas Nast drew many “Caesarism” cartoons in the early 1870s, usually featuring donkeys (as if from Shakespeare’s A Midsummer Night’s Dream; the Democratic donkey symbol would come later).
     
   
Wikipedia: Caesar (title)
Caesar (plural Caesars), Latin: Caesar (plural Caesares), is a title of imperial character. It derives from the cognomen of Julius Caesar, the Roman dictator. The change from being a familial name to an imperial title can be loosely dated to 68 / 69, the so-called “Year of the Four Emperors”.
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Legacy
The history of “Caesar” as an imperial title is reflected by the following monarchic titles, usually reserved for “Emperor” and “Empress” in many languages (note that the name Caesar, pronounced see-zer in English, was pronounced kai-sahr in Classical Latin):
 
Wikipedia: Ulysses S. Grant
Ulysses S. Grant, born Hiram Ulysses Grant (April 27, 1822 – July 23, 1885), was an American general and the eighteenth President of the United States (1869–1877). He achieved international fame as the leading Union general in the American Civil War.
 
Grant first reached national prominence by taking Forts Henry and Donelson in 1862 in the first Union victories of the war. The following year, his celebrated campaign ending in the surrender of Vicksburg secured Union control of the Mississippi and—with the simultaneous Union victory at Gettysburg—turned the tide of the war in the North’s favor. Named commanding general of the Federal armies in 1864, he implemented a coordinated strategy of simultaneous attacks aimed at destroying the South’s ability to carry on the war. In 1865, after conducting a costly war of attrition in the East, he accepted the surrender of his Confederate opponent Robert E. Lee at Appomattox Court House. Grant has been described by J.F.C. Fuller as “the greatest general of his age and one of the greatest strategists of any age.” His Vicksburg Campaign in particular has been scrutinized by military specialists around the world.
 
In 1868, Grant was elected president as a Republican. Grant was the first president to serve for two full terms since Andrew Jackson forty years before. He led Radical Reconstruction and built a powerful patronage-based Republican party in the South, with the adroit use of the army. He took a hard line that reduced violence by groups like the Ku Klux Klan.
 
Presidential experts typically rank Grant in the lowest quartile of U.S. presidents, primarily for his tolerance of corruption. In recent years, however, his reputation as president has improved somewhat among scholars impressed by his support for civil rights for African Americans. Unsuccessful in winning the nomination for a third term in 1880, bankrupted by bad investments, and terminally ill with throat cancer, Grant wrote his Memoirs, which were enormously successful among veterans, the public, and the critics.
 
Wikipedia: Thomas Nast
Thomas Nast (September 27, 1840 – December 7, 1902) was a famous German-American caricaturist and editorial cartoonist in the 19th century and is considered to be the “Father of the American Cartoon.”
 
Caesarism Cartoons
 
Figure Concord
That’s Why They Call it ‘Caesarism’
Michael Ubaldi, May 29, 2003.
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The unwritten rule remained a part of the nation’s conscience, as did its implications. In 1874, whispers that two-term executive Ulysses S. Grant would seek a third term in 1876 were met with cacophonous objection and a rhetorical barrage from Democrats, who accused the president and the Republican Party of “Caesarism,” imperialism, absolutism and every other attribute fitting of a tyrant.
 
Democrat accusations were hysterical enough to make for easy satire by l’auteur terrible du jour Thomas Nast, who characterized the affair in Harper’s Weekly as distended histrionics from a party looking to cast blame for their minority status. Incidentally, the Democrat-leaning newspaper to have begun the “Caesarism” mantra, the New York Herald, had recently fabricated a story about exotic beasts breaking out of the Central Park Zoo (no word on if the author’s last name was “Blair”); and Nast’s cartoon, depicting the Republican vote as an elephant hopelessly unsettled by the donkey’s klaxon, successfully identified the party with the animal, leading to its place as today’s symbol.
 
At any rate, Grant’s aspiration - whether material or not - was defeated.
 
(Oxford English Dictionary)
Cæsarism
[f. CÆSAR + -ISM.]
The system of absolute government founded by Cæsar; imperialism.
1857 O. A. BROWNSON Convert Wks. V. 192 Monarchical absolutism, or what I choose to call modern Cæsarism.
1858 Westm. Rev. Oct. 313 Clumsy eulogies of Cæsarism as incarnate in the dynasty of Bonaparte.
1869 Pall Mall G. 1 Sept. 1 In Napoleon’s Cæsarism there has been no flaw.
1870 JEVONS Elem. Logic vi. 47 The abstract word Cæsarism has been formed to express a kind of Imperial system as established by Cæsar.
1876 BANCROFT Hist. U.S. VI. xxxi. 97 Charlemagne..renewing Roman Cæsarism.
 
17 October 1873, Daily Constitution (Hartford, CT), pg. 2:
An account of Thomas Nast’s first lecture says:—The lecture was illustrated by frequent sketches in colored crayons on a large screen, rapidly drawn and very effective. Andy Johnson was depicted in ermine, crown and royal robes, as an example of “Caesarism,” and facing him the artist drew the ghost of Caesarism in the form of a donkey’s head, laurel-crowned and bodyless—because, as Mr. Nast, observed, Caesar is no-body.