“You are a republic of voices tonight. Unfortunately, that republic is Italy.”

James McHenry diary entry on September 18,1787 https://blogs.loc.gov/teachers/files/2016/09/McHenry-Note.jpg, the day after the signing of the United States Constitution: "A lady asked Dr. Franklin Well Doctor what we got a republic or a monarchy — A republic replied the Doctor if you can keep it."
Attributed

Reply in August 1944 to a statement of regret that the windows of the Hotel de Ville in Paris were not opened for the crowd outside cheering the reestablishment of the Republic. Quoted in The Atlantic, November 1960.
World War II

Letter from Jamaica (Summer 1815)
Context: A state too expensive in itself, or by virtue of its dependencies, ultimately falls into decay; its free government is transformed into a tyranny; it disregards the principles which it should preserve, and finally degenerates into despotism. The distinguishing characteristic of small republics is stability: the character of large republics is mutability.

From a note of uncertain date by Dr. James McHenry. In a footnote he added that "The lady here aluded to was Mrs. Powel of Philada." Published in The American Historical Review, v. 11, p. 618. At the close of the Constitutional Convention of 1787 http://www.bartleby.com/73/1593.html
Constitutional Convention of 1787

New Year's Address to the Nation (1990)

Speech given by Mussolini to a group of Milanese Fascist veterans (October 14, 1944), quoted in Revolutionary Fascism, Erik Norling, Lisbon, Finis Mundi Press (2011) pp.119-120.
1940s

Strangulatus pro republica.
Last written words, two days before he died; these are sometimes reported as being his last words. (17 September 1881) Variant translation: "Tortured for the sake of the republic."
1880s

Book XIV, Chapter 1
The History of Tom Jones (1749)

On New Democracy (1940)
Original: (zh-CN) 国体——各革命阶级联合专政。政体——民主集中制。这就是新民主主义的政治，这就是新民主主义的共和国，这就是抗日统一战线的共和国，这就是三大政策的新三民主义的共和国，这就是名副其实的中华民国。我们现在虽有中华民国之名，尚无中华民国之实，循名责实，这就是今天的工作。