On 30 August Lehwaldt and the Prussian army emerged from the west near the town of Gross-Jägersdorf and attacked the Russians at around 5.00 am. The Prussians were spread thinly in linear formation. They had surprised the Russians on the march and tried to take advantage of the ensuing confusion. Heavy fighting took place in the center lines in the Norkitten Wood, but the Russian artillery took a heavy toll of the Prussians. After four salvoes against the center, the Prussian effort was spent and a general retreat began. The Prussians lost 4,500 men and the Russians lost 6,000. The Russians did not follow up the Prussian retreat, allowing them to leave the battlefield without much molestation. The Prussians, for their part, had a newfound respect for the fighting capabilities of the Russians that was reinforced in the later battles of Zorndorf and Kunersdorf.
The Russians were moving against the East Prussian province by the end of June. East Prussia, isolated from the main Prussian province of Brandenburg/Pomerania, had at its disposal only 32,000 troops under the command of Field Marshal Hans v. Lehwaldt. The Russians, under the overall command of Field Marshal Stephen Fedorovich Apraksin, deployed 55,000 men in five corps along a broad front. They captured the port of Memel on 5 July, and pressed on, intending to march on the East Prussian capital of Königsberg. Lehwaldt decided to attack the Russian columns when they came within striking distance, even though the Prussians, with only 24,000 men, were outnumbered two to one.
A British observer reported that: ‘The Russian troops … can never act with expedition.’ Ponderous drill movements and an almost lethargic attitude to manoeuvre hindered the Russian ability to move troops easily on the battlefield. At Gross-Jägersdorf a Russian observer noted that, ‘Our army was ranged immobile for the whole duration of the combat, with the first rank kneeling and sitting.’ A Prussian reported that’ … although deployment into line has been introduced into their service, the infantry regiment is scarcely capable of arranging a line in less than an hour, and even then the process is always attended with disorder.’
The Russians decided to withdraw from East Prussia and returned to Poland in October. The reasons for this decision are not clear, but Apraksin was removed from his post as a result and ordered to appear at court in St Petersburg. The Prussian field army also left East Prussia, withdrawing to Pomerania to deal with Swedish attempts to seize territory. The Russians returned to East Prussia in January 1758 with 72,000 men and attacked during the winter snows. The Prussians, without the East Prussian field army, offered no real resistance on this occasion, and the Russians took possession of the province, a position they held until the end of the war. As other battles demonstrate, territorial victories were not as important as destroying the field armies of the enemy.