The war followed the internal tensions within Poland where there was the strife between the nobility and the king Stanislaus Augustus Poniatowski, former favorite of the Russian Empress Catherine II. The king was dependent on Russian military backing.
A detachment of Cossacks in Russian service entered Balta (on Ottoman territory) during the pursuit of a Polish Bar Confederation force. The Ottoman Empire accused the troops of having conducted the slaughter of its subjects in the town of Balta, a charge denied by the Russian authorities. Following this border incident at Balta, Sultan Mustafa III declared war on Russia on September 25 1768. The Turks formed the alliance with the Polish oppositionary forces of Bar Confederation, while Russia was supported by the Great Britain, which offered naval advisers to the Imperial Russian Navy.
The Polish opposition was defeated by Aleksandr Suvorov. After that, he was transferred to the Turkish theatre of operations, where in 1773 and 1774 he won several minor and major battles for Russia following the previous successes of the Russian Field-Marshal Count Peter Rumiantsev at Larga and Kagul.
The naval operations of the Russian Baltic Fleet in the Mediterranean yielded even more spectacular victories under the command of Aleksey Grigoryevich Orlov. In 1771, Egypt and Syria rebelled against the Ottoman rule while the Russian fleet totally destroyed the Turkish Navy in the Battle of Chesma.
On July 21, 1774, the Ottoman Empire signed the Treaty of Kuçuk Kainarji. According to the treaty, the Crimean Khanate formally gained its independence (but in reality became dependent on Russia), Russia received the war reparations of 4.5 million rubles and two key seaports allowing the direct access to the Black Sea.
This war was but a small part of the continuous process of expansion of the Russian Empire southwards and eastwards during the 18th and 19th centuries.