Cossacks were a social and military group that by the 10th century settled in southern Russia and present-day Ukraine. They had a Turkic origin and had arrived with hordes of Mongol invasions in the area, settling there permanently. Famous for their combat skills and military strategy, they gradually integrated and mixed with other ethnic groups of Slavic origin.
By the 17th century they were split into Russian Cossacks (which spread to the East) and Ukrainian Cossacks. The latter formed the Zaporozhian Sich state in 1649 (in the Zaporizhia region in the centre-south of today’s Ukraine), and nationalist tradition considers them the founders of the modern Ukrainian nation.
From their stronghold in the fortified Sich of Zaporozhia (or Zaporiyia) they became a fearsome military and political force, resisting and threatening equally the surrounding nations: Poland-Lithuania, Russia and the Ottoman Empire. Finally, in the 18th century, the Russian Empire was responsible for wiping them out once and for all.
But before that, in 1676, the Zaporozhian Cossacks had defeated the troops of Ottoman Sultan Mehmed IV at the battlefield. However, he continued to insist that they subdued to his authority, and sent them an ultimatum:
Sultan Mehmed IV to the Zaporozhian Cossacks:
As the Sultan; son of Muhammad; brother of the sun and moon; grandson and viceroy of God; ruler of the kingdoms of Macedonia, Babylon, Jerusalem, Upper and Lower Egypt; emperor of emperors; sovereign of sovereigns; extraordinary knight, never defeated; steadfast guardian of the tomb of Jesus Christ; trustee chosen by God Himself; the hope and comfort of Muslims; confounder and great defender of Christians – I command you, the Zaporogian Cossacks, to submit to me voluntarily and without any resistance, and to desist from troubling me with your attacks.
The Cossacks, under the command of Otaman Ivan Sirko, responded to the Sultan with a letter that has entered the history of diplomacy (and eschatology) with honors:
Zaporozhian Cossacks to the Turkish Sultan!
O sultan, Turkish devil and damned devil’s kith and kin, secretary to Lucifer himself. What the devil kind of knight are thou, that canst not slay a hedgehog with your naked arse? The devil shits, and your army eats. Thou shalt not, thou son of a whore, make subjects of Christian sons; we have no fear of your army, by land and by sea we will battle with thee, f##k thy mother.
Thou Babylonian scullion, Macedonian wheelwright, brewer of Jerusalem, goat-fu##er of Alexandria, swineherd of Greater and Lesser Egypt, pig of Armenia, Podolian thief, catamite of Tartary, hangman of Kamyanets, and fool of all the world and underworld, an idiot before God, grandson of the Serpent, and the crick in our dick. Pig’s snout, mare’s arse, slaughterhouse cur, unchristened brow, screw thine own mother!
So the Zaporozhians declare, you lowlife. You won’t even be herding pigs for the Christians. Now we’ll conclude, for we don’t know the date and don’t own a calendar; the moon’s in the sky, the year with the Lord, the day’s the same over here as it is over there; for this kiss our arse!
– Koshovyi otaman Ivan Sirko, with the whole Zaporozhian Host.
Unfortunately the original letter has never been found, so this whole episode was long considered a legend. But in 1870 an ethnographer named Novitsky found a copy dated 18th century in the city of Dnipró. It is written in Russian, explicitly indicating that it is a translation from Polish (it is possible that Polish here means Ukrainian, as there was no denomination for this language then).
Some researchers believe that it would really be a parody of a response to the letters that the king of Poland received from the sultan in the same sense, thus created by the Polish elite as fun. But others, such as the Ukrainian Pavel Tarkovsky, maintain that it is authentic and was written by Cossacks. As long as a copy is not found in the Turkish archives we will never know the truth.
We will have to settle for the picture painted in 1891 by the Russian artist Iliá Repin and titled precisely Reply of the Zaporozhian Cossacks to Sultan Mehmed IV of the Ottoman Empire, where he shows the amusing scene of composition of the missive. The painting was acquired by Tsar Alexander III for 35,000 rubles, the largest sum then paid for a Russian painting, and is now on display at the Russian State Museum in St. Petersburg.
Sources: The Cossack Letter / Friedman, Victor A. (1978), The Zaporozhian Letter to the Turkish Sultan: Historical Commentary and Linguistic Analysis / Early Ukraine: A Military and Social History to the Mid–19th Century (Alexander Basilevsky) / Wikipedia.