The battle of Jonkowo (3 February 1807) was an inconclusive battle that allowed the Russians to escape from a trap set for them by Napoleon after the Russians attempted to attack the left flank of the French army in Prussia.
The battle took place at a village referred to in contemporary accounts of the battle as Jonkowo. The German name of the village was Jonkendorf. Some accounts of the battle call it Ionkovo or Jonkovo.
After defeating Prussia at Auerstadt and Jena on 14 October 1806 Napoleon turned east to deal with the Russians, the last major players of the Fourth Coalition still active in central Europe. In November he occupied Warsaw and crossed the Vistula. The Russians attempted to hold the line of the Rivers Ukra and Bug, north-east of Warsaw, but the French managed to cross the Ukra on 23 December 1806 (combat of Czarnowo) and the Russians began to retreat. The French pursued, but the battles of Pultusk and Golymin (both 26 December 1806) were both inconclusive and on 28 December Napoleon ordered his men into winter quarters.
The French army was spread out from Warsaw to the Baltic coast. Bernadotte was at the far left, with Ney to his right. Soult, Davout and Lannes were posted to the north and east of Warsaw, around the River Narew and Bug. Augereau was posted to the north-west of Warsaw, with the River Ukra as his eastern limits. The Russians took up a position further up the River Narew.
Napoleon expected the Russians to remain in winter quarters, but at a conference of war on 2 January the Russians decided to go onto the offensive. Their plan was to move most of their army north, hiding behind the Forest of Johannesburg. They would then turn west and advance through East Prussia to attack Bernadotte. During the early stages of this movement General Bennigsen was given sole command of this army.
At first the Russian plan went well. They were able to move north without being detected, and by mid-January they were moving west towards Bernadotte. Their plan was disrupted by the unauthorised movements of Marshal Ney. He decided to probe north towards Konigsberg, and by 19 January elements of his cavalry were at Schippenbeil, on the River Alle. This was well to the north of the area Napoleon had placed them, and put them between Bernadotte in the west and the advancing Russian army. On 19 January the leading Russian forces ran into this outlying French force. Ney was forced to retreat, but he sent a warning to Bernadotte, who was able to concentrate enough of his men to inflict a defeat on the Russians at Mohrungen (25 January 1807). Despite this success Bernadotte was forced to retreat. Bennigsen occupied Mohrungen, and then decided to rest for a few days to allow his army to recover from their long march.
Once Napoleon learnt about the Russian attack he realised that this gave him a chance to win a decisive victory. Davout, Soult, Augereau and Murat with the cavalry were all ordered to move north. Bernadotte was to move slowly south to join up with the advancing troops coming north.
Napoleon's plan might have had a good chance of success, but on 31 January the messenger taking a copy of the orders to Bernadotte was captured and was unable to destroy his dispatches. On 1 February the French orders were presented to Bennigsen who realised that he would have to retreat if he was to avoid destruction.
By 3 February the Russians had pulled back to Jonkowo. The Russian centre was close to the village, their right in a marshy wooded valley and their left at Mondtken (modern Matki), close to the River Alle. Count Nikolai Kamenski, the son of the former army commander, was posted at Bergfried (modern Barkweda), to guard a key bridge over the Alle. He commanded his own division and may have had support from a second division.
Early on 3 February Ney and Augereau found the Russian rearguard under Barclay de Tolly on the road from Allenstein towards Jonkowo, and pushed them back towards the main force. Napoleon rushed to the scene and despite only having a small part of his army available decided to attack. At the start of the battle Napoleon had two divisions from Ney's corps, three from Soult's corps, part of the Guard and part of Murat's Reserve Cavalry. Augereau's corps was approaching the area, but wasn't yet present.
Napoleon's plan was for Soult to take two divisions to attack the Russians at Bergfried and then fall on the Russians from their left-rear. In the centre Napoleon engaged in an artillery bombardment designed to pin the Russians in place at Jonkowo and prevent them from sending reinforcements to Kamenski.
The main part of the battle thus took place at Bergfield, and is sometimes described as the Combat of Bergfield. The Russians had four battalions at Bergfield, supported by three Prussian gun batteries. One of the battalions defended the village of Bergfield, which was on the east bank of the river.
Soult decided to launch a two-pronged assault on the Russian position. The 24th Light attacked the village itself while the 4th Line and a battalion of the 28th was sent north in an attempt to ford the river. The first attack on the village was repulsed, but a second attack pushed the Russians out of the village and across the bridge. The Russians then counterattacked and retook the bridge. The outflanking force struggled to find a place to cross the river, which was frozen but covered in several feet of soft snow. By the end of the day Soult had secured a foothold across the Alle, and part of his force camped on the west bank, but the Russian defence meant that darkness fell before the French were able to take advantage of any successes.
The French were able to advance up the river to Guttstädt (now Dobre Miasto) where they captured part of the Russian baggage train. Their foothold over the river also meant that the Russian position at Jonkowo was no longer tenable, and so on the night of 3-4 February Bennigsen retreated north, moving towards Landsberg and Preussich Eylau. Napoleon finally got his full scale battle at Eylau (7-8 February 1807), but this costly battle was also inconclusive, and the two sides finally went into winter quarters.