“Once a gentleman, and always a gentleman.”

The Late Late Show with Craig Ferguson (2005–2014)

Speech to his crew off of Puerto San Julian, Argentina, prior to entering the Strait of Magellan (May 1578)
Context: For by the life of God, it doth even take my wits from me to think on it. Here is such controversy between the sailors and gentlemen, and such stomaching between the gentlemen and sailors, it doth make me mad to hear it. But, my masters, I must have it left. For I must have the gentleman to haul and draw with the mariner, and the mariner with the gentleman. What! let us show ourselves to be of a company and let us not give occasion to the enemy to rejoice at our decay and overthrow. I would know him that would refuse to set his hand to a rope, but I know there is not any such here...

Source: Pride and Prejudice

Talking to Gyula Andrássy in Salzburg on 18 September 1877. As quoted in Disraeli, Gladstone, and the Eastern Question. A Study in Diplomacy and Party Politics (1935) by Robert William Seton-Watson, p. 224 books.google http://books.google.de/books?id=5CPVAAAAMAAJ&q=fox; "Schlaukopf" is translated elsewhere as "clever dick" or "smart aleck."

With deal (instead of do) with a pirate, in Prime Minister Gyula Andrássy's influence on Habsburg foreign policy during the Franco-German War of 1870-1871 (1979) by János Decsy, p. 21 http://books.google.de/books?id=JtUhAAAAMAAJ&q=111

„Man behandelt mich wie einen Fuchs, wie einen Schlaukopf erster Klasse. Die Wahrheit aber ist, qu'avec un gentleman je suis toujours gentleman et demi, et que quand j'ai affaire à un corsaire, je tâche d'etre corsaire et demi"
:Eduard von Wertheimer: Graf Julius Andrássy. Sein Leben und seine Zeit. Vol. III. Deutsche Verlags-Anstalt Stuttgart 1914 pp. 42-43 http://books.google.de/books?id=2skhAAAAMAAJ&q=demi
1870s

"Platinum Men", Metro Him, 2007 September-November, p. 66.
2007