Siege of Kolberg ( Seven Years ' War ) During the Seven Years ' War , the Prussia n - held town of Kolberg in Brandenburg - Prussian Pomerania ( now Kołobrzeg ) was besieged by Russia n forces three times . The first two sieges , in late 1759 and from 26 August to 18 September 1760 , were unsuccessful . A final and successful siege took place from August to December 1761 . In the sieges of 1760 and 1761 , the Russian forces were supported by Swedish auxiliaries . As a consequence of the fall of the city , Prussia lost her last major port on the Baltic Coast , while at the same the Russian forces were able to take winter quarters in Pomerania . However , when Empress Elizabeth of Russia died only weeks after the Russian victory , her successor , Peter III of Russia , made peace and returned Kolberg to Prussia . First siege ( 1759 ) . A first siege in 1759 was repelled by the Prussian defenders . Russian Count Fermor was ordered to expel the Prussian forces commanded by Count Dohna from Pomerania , take Kolberg and establish winter quarters in Brandenburg - Prussian Pomerania . Fermor reluctantly pursued his objectives , regarding full achievement nearly impossible . Fermor dispatched 4 , 000 troops and 20 artillery pieces , commanded by Lieutenant - General Johann Palmenbach to siege Kolberg , defended by 700 regulars and a levy , commanded by Heinrich Sigismund von der Heyde who had just upgraded the defense works and stocked supplies . Siege was laid on 4 October . Though Russian reinforcements brought up Palmenbach strength to 5 , 000 the following month , heavy rain and storm rendered successful construction of siegeworks impossible . In addition , twenty - seven Russian warships arrived to assist the siege from the seaside , yet throughout October , storms wrecked twenty - one , and none came close enough to participate . The siege was lifted on 1 November . Second siege ( 1760 ) . The Russia n forces had the objective to establish their 1760 / 61 winter quarters near the lower Oder , which could only be achieved by securing the fortress of Kolberg . In July , a Russian expedition commanded by Gottlob Heinrich Tottleben advanced into Brandenburg - Prussian Pomerania , but upon reaching the Rega valley was ordered to the Silesian battlefields . On 27 August , Kolberg was bombarded from the sea by the entire Russian Baltic fleet : twenty - one ships of line , three fregattes and three bomb vessels , all of them had arrived the day before . On 29 August , they were joined by six ships of line and three frigates of their Swedish allies . Some 8 , 000 troops were deployed and started constructing siege works on 6 September , covered by cavalry units . The Prussian defense was commanded by Colonel Heinrich Sigismund von der Heyde . Frederick II of Prussia ordered a force of 3 , 800 commanded by Major - General Hans Paul Werner to disengage from the battles in Silesia and instead relieve Kolberg , which was some to the North . After a 13 day ride , Werner ' s force arrived the Russian lines on 18 September and attacked immediately . A successful skirmish made the besiegers believe they were dealing with a force of up to 20 , 000 and led them to withdraw on board of their vessels . The Swedish and Russian ships left on 20 and 23 September , respectively . Russian casualties amounted to 600 troops . After the battle , Frederick promoted both Werner and Heyde to the rank of a Lieutenant - General . Third siege ( 1761 ) . Tottleben , who had commanded the Russian spring campaigns in Pomerania the year before , committed treason and revealed to Frederick the Russian plans to siege Kolberg again in 1761 . Once Frederick was aware of this , he ordered supplies to the fortress , withdrew prince Friedrich Eugen of Württemberg from the Swedish front in Mecklenburg . Württemberg reached Kolberg on 4 July , where he commanded a reinforced defense force of 12 , 000 troops . Russian commander Pyotr Alexandrovich Rumyantsev - Zadunaisky , commanding a weaker force , took quarter in nearby Köslin ( now Koszalin ) on 23 June , awaiting reinforcements . Württemberg ' s plan to attack Rumyantsev as long as the odds favoured Prussia was cancelled by Frederick as too risky . After 3 , 000 Russian troops had reinforced Rumyantsev in mid - August , he laid siege to Kolberg on 22 August . Twenty - three Russian warships assisted Rumyantsev at this points , an additional eight Swedish warships joined later . The town was continuously bombarded from 25 August to 25 September . On 18 September , Rumyantsev stormed Württembergs defense outside the town , suffering 3 , 000 casualties with little ground gained . He then changed his strategy from preparing storms to cutting off Kolberg from supplies . On 30 September , Kolberg was reinforced by several thousand Prussian troops commanded by Dubislav Friedrich von Platen . With the reinforcements , the fortress was defended by nearly 20 , 000 Prussians . Rumyantsev , who lost naval support on 9 October when the Russian warships sailed home because of bad weather , was reinforced by part of Alexander Borisovich Buturlin ' s army the same month . His cavalry , commanded by Gustav Berg , cut off Prussian communication lines , countered excursions of Württemberg ' s 2 , 700 horse and captured at least four their units . As the Prussians were running out of supplies , Platen ' s force was ordered to Berlin in late October . In November , Württemberg abandoned Kolberg , broke through the Russian lines to reunite with Platen , and then attempted to rout Rumyantsev from the rear . When Platen and Württemberg did not succeed , Platen departed as ordered , and Württemberg tried several times to force his way back into the fortress . On 12 December , the Russian forces halted his final attempt at Spie , some kilometers southwest of Kolberg , inflicting 1 , 000 casualties on his force . Württemberg ' s remaining 8 , 000 troops thereupon retreated to Stettin . On 16 December , Kolberg capitulated to Rumyantsev , enabling his forces to take winter quarter in Brandenburg - Prussian Pomerania . Another Russian achievement was that Rumyantsev ' s siege kept Platen ' s forces in check , whom hard - pressed Frederick had expected to aid him in Silesia once Kolberg was relieved . By the time Platen escaped the pocket , the setbacks Frederick suffered in Silesia were already irreversible , thus Platen was ordered to Berlin instead to support his Saxon ally . Aftermath . By the time of the sieges , Russian Tsaress Elizabeth of Russia was suffering from an illness which led to her death on 25 December 1761 ( OS ) or 5 January 1762 ( NS ) . Elizabeth was succeeded by her nephew , Peter III of Russia , an admirer of Frederick partially raised in Berlin . Peter , who had opposed Russia ' s anti - Prussian involvement in the Seven Years ' War , ceased the hostilities with Prussia at once , and by the terms of the Treaty of Saint Petersburg returned to her all occupied territories ( including Kolberg ) and provided Frederick with 20 , 000 troops . Deprived of their Russian ally , the Austrian House of Habsburg was unwilling to continue the war on their own , and returned to the " status quo ante " with Prussia in the Treaty of Hubertusburg .