East Pomeranian Offensive The East Pomeranian Strategic Offensive operation ( ) was an offensive by the Red Army in its fight against the German " Wehrmacht " on the Eastern Front . It took place in Pomerania and West Prussia , and officially lasted from 10 February – 4 April 1945 . In Soviet reckoning , it involved the following subordinate operations : Planning . The 2nd Belorussian Front — under Konstantin Rokossovsky — had initially been tasked with advancing westward north of the Vistula River toward Pomerania and the major port city of Danzig , with the primary aim of protecting the right flank of Zhukov ' s 1st Belorussian Front , which was pushing toward Berlin . During the East Prussian Offensive , however , Rokossovsky was ordered to wheel directly north toward Elbing . This left substantial German forces intact in Pomerania , where they threatened the right flank of Zhukov ' s formations . As a result , once the initial phase of the East Prussian Offensive was over , the 2nd Belorussian Front was redeployed with the intention of attacking westwards into Pomerania , eliminating the possibility of a German counter - offensive ( similarly , the parallel Silesian Offensives of Konev ' s 1st Ukrainian Front in the south were in part designed to protect the 1st Belorussian Front ' s left flank ) . The need to secure the flanks delayed the Soviets ' final push towards Berlin , which was originally planned for February , until April . Joseph Stalin ' s decision to delay the push toward Berlin from February to April has been a subject of some controversy among both the Soviet generals and military historians , with one side arguing that the Soviets had a chance of securing Berlin much quicker and with much lower losses in February , and the other arguing that the danger of leaving large German formations on the flanks could have resulted in a successful German counter - attack and prolonged the war further : the Germans did in fact mount a surprise counter - attack in Pomerania in mid - February , Operation Solstice . The delay did , however , allow the Soviets to occupy significant parts of Austria in the Vienna Offensive . German intelligence . As early as 13 February , German intelligence services had deduced that the Soviets would seek to clear Pomerania before advancing on Berlin . The 2nd Army — defending a large and exposed sector running through Pomerania eastward toward the edge of East Prussia at Elbing — sought permission to withdraw , but this was denied by Adolf Hitler . Grudziądz , on the Vistula , was surrounded on 18 February ( the garrison , from the 83rd Infantry Division — finally surrendered the following month ) . Deployments . Wehrmacht . The corps of the Second Army were seriously understrength by this time , being composed largely of fragmentary or " ad hoc " units . The 3rd Panzer Army had been rebuilt using the " korps " of the recently - formed 11th SS Panzer Army , the original formation having been largely destroyed in Lithuania and East Prussia , where its remnants were now defending Königsberg . The offensive . Breakthrough . Rokossovsky opened the offensive on 24 February using the fresh troops of Kozlov ' s 19th Army , but after an initial advance of some they were halted by intense German resistance . On 26 February , he inserted the 3rd Guards Tank Corps east of Neustettin , where they achieved a penetration of , and relieved Kozlov of command . The 3rd Guards Tank Corps broke through at Baldenburg , while Neustettin on the Front ' s left flank fell to the 3rd Guards Cavalry Corps on 27 February . Weiß had hurriedly assembled the VII Panzer Corps , including the remnants of the 7th Panzer Division , at Rummelsberg to threaten 19th Army ' s flank . However , after a Soviet breakthrough at Koslin on 2 March , the 2nd Army found itself completely cut off from the rest of its Army Group . 1st Belorussian Front joins the attack . Zhukov ' s right wing — a grouping of the 3rd Shock Army and 1st and 2nd Guards Tank Armies — went over to the offensive on 1 March , striking northward with the main force concentrated at Reetz . The entire left wing of 3rd Panzer Army was cut off by their breakthrough , after Guderian refused Raus ' request for withdrawal ; the right flank withdrew towards Stettin . On 4 March , forward Soviet tank units reached the Baltic , and the German forces in Pomerania were trapped in a series of encirclements . The 2nd Army began to fall back on the Danzig fortified area , while the X SS Corps of the 3rd Panzer Army had been surrounded at Dramburg . The second phase . Rokossovksy opened the second phase of his offensive on March 6 . The 2nd Shock Army threatened to cut off the defending forces in the fortress of Marienburg , which was evacuated two days later , while in the east Elbing finally fell on 10 March . Weiß , having warned that the Elbing pocket could not be held , was relieved of command on 9 March and replaced by Dietrich von Saucken . The troops of the German 2nd Army withdrew in disarray into Danzig and Gdynia , where the 2nd Belorussian Front besieged them . Zhukov ' s forces meanwhile , cleared the remainder of 3rd Panzer Army from the east bank of the lower Oder , driving the Germans from their last positions in a bridgehead at Altdamm . Siege of Kolberg . Many civilian refugees from Pomerania had fled into the coastal town of Kolberg , which was surrounded by 4 March . Nevertheless , the town was successfully defended until 18 March , by which time evacuation was almost complete . Siege of Danzig . The Danzig - Gotenhafen ( Gdynia ) Fortified Area — also the main port for refugees from East Prussia escaping to the west — was ordered to be defended for as long as possible by von Saucken in order to keep open evacuation routes . Rokossovsky opened his final offensive on 15 March 1945 ; the main thrust , toward the coast at Zoppot between Gdynia and Danzig , being undertaken by the 70th and 49th Army advancing in parallel . The fighting was savage , but by 19 March 1945 the Soviet spearheads had reached the heights over Zoppot , while the 4th Panzer Division had been pushed back to the outskirts of Danzig itself . By 22 March 1945 , the 70th Army reached the sea , splitting the German defence . Gdynia was taken on 26 March 1945 , its defenders and many civilians retreating to the headland at Oksywie , from where they were evacuated to the Hel Peninsula . Danzig finally fell on 28 March 1945 , after which the remnants of the 2nd Army withdrew to the Vistula delta north - east of the city . Evacuation of civilians and military personnel from there and from the Hel Peninsula continued until 10 May 1945 . The Soviets declared the East Pomeranian Offensive complete a week after the fall of Danzig . According to Soviet information , in the Battle of Danzig the Germans lost 39 , 000 soldiers dead and 10 , 000 captured .