This happened during the war of the second anti-French coalition of 1798-1802. At the beginning of the campaign, the French subjugated almost all of Italy.
Russia, Austria and Great Britain could not allow such an expansion of French influence. The Apennine Peninsula became a field of fierce struggle.
The Russian army, led by the brilliant Field Marshal Alexander Suvorov, fought successfully in the north of Italy, while the Russian fleet under the command of the equally talented Admiral Fyodor Ushakov operated in the Mediterranean Sea and landed troops on the southern coast.
Thanks to one of these landings in May 1799, the French lost Naples. In the fall, it was Rome's turn.
A detachment of 800 bayonets under Colonel Anton Skipor advanced to the "eternal city". In addition to the 2,000-strong French garrison, there were forces of local pro-French republicans in Rome.
However, when the enemy learned of the approach of the Russians, it immediately capitulated. However, it surrendered not to Ushakov, but to Horatio Nelson's English squadron operating in that area.
The insulted admiral ordered Skipor to leave for Naples, but soon received a request from the cardinals to send Russian soldiers to Rome anyway – to maintain order there. Which happened on October 11, 1799.
"The delight with which the residents greeted us brings the greatest honor and glory to the Russians. From the very gates of St. John to the soldiers' quarters, both sides of the streets were dotted with inhabitants of both sexes. Our troops could hardly pass. ‘Vivat Pavlo primo (Russian emperor Paul I)! Vivat Moscovito!’ was proclaimed everywhere with applause," reported Lieutenant Pyotr Balabin.
The Russians remained in the city for some time and then went to liberate Malta from the French.