The Russian fleet left Kronstadt on May 15 under Admiral Thomas Gordon, who had his flag on the 100-gun ship Peter I and II. For reconnaissance the admiral sent out the 32-gun frigates Russia and Mitau. Ten days later the frigate Mitau, commanded by Captain Pyotr Defremery, was taken unawares by the French 60-gun Fleuron and 46-gun Gloire. At the insistence of the French, Cap-tain Defremery came on board the Fleuron and was then arrested. The Russian frigate Mitau, left without its captain, was seized. Admiral Gordon, meanwhile, arrived at Danzig with the fleet on 1 June. Having failed to repulse the reinforcements, the French surrendered on 13 June. Leshchinsky escaped from Danzig, the town was occupied by Russian troops and the French gave up their frigate the Brilliant. The dispute over the Polish throne ended in favour of August III.
The Swedes had not forgotten their defeat in the Northern War, and for twenty years had awaited an opportunity for revenge. At last, in 1741 the Swedish government acted, albeit unwisely. They managed to send only twelve ships of the line to the Gulf of Finland, while the Russian fleet had armed fourteen out of 27 ships of the line. In 1741 no sea engagement occurred. The Russian ships were anchored off shore, and the Swedes never attacked. The Russian army had acted decisively. Supported by the galley fleet, the land forces inflicted a heavy defeat upon the enemy at Vilmanstrand.
In August 1742 the land forces of General Field Marshal Pyotr Lassy, advancing along the Finnish coast, compelled Helsingfors Fortress (modern-day Helsinki) and its Swedish garrison of 17,000 to surrender. The left flank of Lassy's army was sup-ported by 44 galleys and a landing force of 10,000 men. To screen the galleys, a flotilla under Vice-Admiral Zakhary Mishukov was sent from Kronstadt. Mishukov approached the Swedish fleet of Vice-Admiral Sjostjerna, which, having earlier retreated from the Aspo skerries to Gangut Peninsula, had opened the way to the Russian galleys. Both commanders, each with fourteen ships of the line, showed determination to fight but passed clear of each other without firing a single cannon. The Russian ships headed for Revel and the Swedes, for Karlskrone. Although no shots were fired, losses were nevertheless incurred when the 32-gun Russian frigate Hector and the Swedish 54-gun ship of the line Oland were wrecked in a fierce storm.
The campaign of 1743 began in May with a battle between the two prams (armed ships for use in shallow water) and seven galleys of Russian Captain Ivan Kaysarov against the one pram and eighteen galleys of Swedish Vice-Admiral Falkengren. The stubborn fight off Korpostrem Island lasted three hours, after which the Swedes retreated to the Aland Islands, where the galley fleet of General Field Marshal Lassy, 133 vessels with a landing force, was awaiting the Swedish invasion.
To block the way to the Russian galleys, the Swedes advanced sixteen ships of the line under Admiral von Utfahl. Off Gangut they were met by Russia's Baltic fleet, sent from Kronstadt, under Admiral Nikolay Golovin, who commanded fifteen ships of the line. Golovin was sailing on board the Saint Peter. On 6 June the two formidable forces were ready for battle. It was foggy and the sea was calm. Golovin fired several guns, and the Swedes responded. The range was long, and the cannonballs fell into the water, not striking their intended targets. Golovin never actually attacked the Swedes, but his maneuvres diverted von Utfahl from Gangut. Lassy's galleys were no longer obstructed, and on 15 June he reached the Aland Islands and received a communication asking for peace. The Abo Peace Treaty was signed soon thereafter and, according to its terms, Russia not only retained its former territories, but also gained a part of Finland up to the Kymin River.
By the beginning of the Seven Years War (1756-1762), the government of Empress Elizabeth had, to some extent, succeeded in strengthening the Russian fleet. However, her fleet commander's strategies proved unsuccessful. While the enemy did not resist, fleet commander Admiral Mishukov did well. However, in August 1760, during a landing at the Prussian fortress of Kolberg, the fleet lost 22 guns, and 600 men were taken prisoner, due to an unwise decision on his part.
The following year Vice-Admiral Andrey Polyansky brought nineteen ships of the line and 7,000 landing troops to Kolberg. On land Polyansky was supported by commander Major-General Pyotr Rumyantsev. On 6 December the Prussians surrendered to Rumyantsev. The Russian command captured 30 banners, 146 guns and nearly 3,000 enemy prisoners.