After defeating the
Prussian army in the autumn of 1806,
Emperor Napoleon entered
partitioned Poland to confront the Russian army, which had been preparing to support the Prussians until their sudden defeat. Crossing the River
Vistula, the French advance corps took
Warsaw on 28 November 1806.
The Russian army was under the overall command of
Mikhail Kamensky, but he was old and becoming infirm. The Russian First Army of some 55,000 to 68,000 men,
 commanded by Count Bennigsen, had fallen back from the Vistula to the line of the River
 in order to unite with the Second Army, about 37,000 strong,
 under General
Friedrich Wilhelm von Buxhoeveden (Buxhöwden), which was approaching from Russia and was still several days march from the First Army. However, realising his mistake in allowing the French to cross the Vistula, Kamensky advanced at the beginning of December to try to regain the line of the river.
 French forces crossed the
Narew River at
Modlin on 10 December, and the Prussian Corps commanded by
Anton Wilhelm von L'Estocq failed to retake
Thorn (Toruń). This led Bennigsen on 11 December to issue orders to fall back and hold the line of the River Wkra.
When this was reported to Napoleon, he assumed the Russians were in full retreat. He ordered the forces under Marshal
Joachim Murat – the 3rd corps of Marshal
Louis Nicolas Davout, 7th Corps of Marshal
Pierre Augereau, 5th Corps under Lannes, and Murat's 1st Cavalry Reserve Corps – to pursue towards
Pułtusk. Meanwhile, Marshal
Michel Ney's 6th Corps, Marshal
Jean-Baptiste Bernadotte's 1st Corps, and Marshal
Jean-Baptiste Bessières's 2nd Cavalry Reserve Corps turned the Russian right. Marshal
Nicolas Soult's 4th Corps linked the two wings of the French army.
Kamensky reversed the Russian retreat, and he ordered an advance to support the troops on the River Wkra.
 On the night of 23 and 24 December, Davout's corps forced a crossing of the lower Wkra in the
Battle of Czarnowo.
 After engagements at
Bieżuń on 23 December with Bessières and
Soldau (Działdowo) on 25 December with Ney, the Prussian corps under L'Estocq was driven north towards
 Augereau's corps seized a second crossing of the Wkra on the 24th at
 Realising the danger, Kamensky ordered a retreat on
Ostrołęka. At this time the old field marshal appears to have had a mental breakdown and returned to
Grodno. Bennigsen decided to disobey his superior's orders by standing and fighting on 26 December at Pułtusk. He had available the 2nd Division of
Alexander Ivanovich Ostermann-Tolstoy, the 6th Division of Lieutenant General Alexander Karlovich Sedmoratski, part of Lieutenant General
Dmitry Golitsyn's 4th Division, and part of Lieutenant General
Fabian Gottlieb von Osten-Sacken's 3rd Division. To the north-west, most of the 4th Division commanded by Golitsyn and the 5th Division under Lieutenant General
Dmitry Dokhturov fought the
Battle of Gołymin on the same day.
The weather caused severe difficulties for both sides. Mild autumn weather had lasted longer than normal.
 The usual frosts, which rendered the inadequate roads passable after the muddy conditions of autumn, were broken by thaws. There was a thaw on 17 December
 and a two-day thaw on 26 and 27 December.
 The result was that both sides found it very difficult to manoeuvre; in particular the French (as they were advancing) had great difficulty bringing up their artillery.
Davout recorded it took two hours to cover 2½ miles.
There were also difficulties with supply. Captain
Jean-Baptiste-Antoine-Marcelin, Baron de Marbot, who was serving with Augereau's Corps wrote:
||It rained and snowed incessantly. Provisions became very scarce; no more wine, hardly any beer, and what there was exceedingly bad, no bread, and quarters for which we had to fight the pigs and the cows.
Pułtusk lies on the west bank of the River
Narew with a suburb on the east bank. The road from Strzegociz crossed the river by a bridge and then ran north-west towards
Gołymin. A second road from Warsaw entered the town from the south-west, and then ran along the west bank of the river towards
Różan. Before it reached Pułtusk this road was joined by one from
Nasielsk. Another longer route to Różan ran along the east bank. The final road was that to Markow, which ran northwards from the town. The town itself lay on low ground. To the north and west lay a plateau, narrowing to a wide ridge nearer the river. A ravine cut into the plateau near the river. A large wood lay on the north-west side of the plateau, towards the village of Mosin. Further out from the plateau more woods covered the approaches from Warsaw.