Russian troops retained a numerical advantage over the Germans, the supply of shells made it possible to conduct an intense battle for several days. However, the German and Austro-Hungarian troops of the army of
Remus von Woyrsch managed to force the Vistula River above
Ivangorod and create a threat to the rear of the Ivangorod fortress and the Russian 2nd Army. On August 2, M. Alekseyev gave the order to stubbornly defend the line of Warsaw forts and
Praga (a suburb of Warsaw on the right bank of the Vistula River), but in the evening he ordered to withdraw the 2nd Army on the night of August 3 to the right bank of the Vistula, retaining only the line of forts, but not waging a stubborn battle on it, but only, if possible, delaying the Germans. As a result, both the 1st and 12th Russian armies had to take measures for the timely withdrawal of units so as not to be cut off by the breakthrough of the armies of the Central Powers from the south. The garrison of the Novogeorgievsk fortress, now subordinate directly to M. Alekseyev; on August 3, it began to be withdrawn from advanced positions to the forts of the outer bypass. Covering the withdrawal of the 2nd, 4th and 3rd armies was assigned to the 1st and 12th armies. In the Russian 12th Army on August 3, a stubborn battle continued along the entire front, while the
4th Siberian Army Corps was again thrown back. German troops captured 2,000 prisoners and 14 machine guns. On August 4, after 14:00, the Germans attacked with large forces and broke through the positions of the
1st Siberian Army Corps and threw back the left flank of the 1st Siberian Army Corps of the 12th Army. The losses suffered were so great that at midnight on August 5, the commander of the 1st Army ordered the right flank of the army to be withdrawn with the withdrawal of the
IV Corps to the army reserve. During the day the German onslaught continued. Actions in the sector of the 12th Army were also fierce. On August 4-5, Russian troops stubbornly defended their positions along the Orzyc river, constantly conducting counterattacks, but by the evening they were pushed back. On the night of August 5, Russian troops of the 2nd Army left Warsaw, blowing up railway stations and bridges across the Vistula River. In the morning, the troops of the German 9th Army, led by Field Marshal
Prince Leopold of Bavaria, entered the capital of the Kingdom of Poland. On August 6, the army group of M. von Gallwitz was transformed into the 12th Army. To strengthen the offensive on the left flank of the army, the
XI Corps was transferred. In three days, Russian troops were driven back at a front of 25 km to 4-7 km to the east, they lost 85 officers and 14,200 soldiers as prisoners, 6 guns, 8 mortars, 69 machine guns. On August 7, the 12th Army's 1st Army Corps was again attacked and left the northern part of
Szczepankowo. Following the 12th Army, under pressure from the German's (
XIII and
XVII Corps), the right flank of the 1st Army began to retreat. By the morning of August 8, the 1st Army also made a withdrawal. As a result of the retreat of the 1st and 2nd Armies, the Novogeorgievsk fortress was blocked from the south by the division of Lieutenant General Thilo von Westernhagen from the German 9th Army. Ludendorff sent von Galwitz an order for a “parallel pursuit” of Russian troops along the Bug River in order to intercept their retreat to the east. The capture of Novogeorgievsk was entrusted to the siege corps of
Hans Hartwig von Beseler, while Ludendorff insisted on attacking the fortress from the east, from the confluence of the Bug and Vistula, while Gallwitz considered it more convenient to attack from the north, where there were no water barriers. Having discovered the withdrawal of Russian troops, the German 12th Army, on the morning of August 8, turned to pursuit. Pressure continued on the left flank of the Russian 12th Army. The heavy casualties of the Russian 12th Army (up to 80,000 men, of which 30,000 were killed and captured) forced its commander to decide to withdraw, despite the objections the chief of the staff of the North-Western Front. The 33rd and
78th Divisions were completely destroyed, only 380 men remained in the brigade of the
44th Division. The situation with ammunition became more complicated: 140 shells remained for a light gun, 101 - for a corps mortar, 56 - for a heavy howitzer, and 86 - for a heavy gun. Only 4,100 shells for field and 652 for heavy guns remained in the 12th Army. The situation was complicated by the offensive of the German 9th Army, which crossed from Warsaw to the right bank of the Vistula River. By the evening of August 10, the Russian 1st and 12th armies retreated to new positions, the Germans completely captured the Łomża fortress, and entrenched themselves on the banks of the Bug River. But the onslaught on the junction of the Russian armies continued. On the night of August 11, the 12th Army retreated from the bend of the Narew River. Von Gallwitz was preparing to continue pushing through the junction of the Russian armies, but E. Ludendorff categorically ordered the direction of the attack to be shifted to the right flank - along the right bank of the Bug River. On August 11, the German XVII and XIII Corps pushed back parts of the 1st Siberian and 21st Army Corps beyond Zuzel and towards
Czyżew. The XI and I Corps again defeated the 4th Siberian and 5th Army Corps. The German 8th and 12th Armies received a new task: to advance on
Bielsk Podlaski. On August 12, the German 8th Army attacked the positions of the 1st Army Corps of the Russian 12th Army, the German
75th Reserve Division advanced 20 km at once. The 4th Siberian Army Corps, reinforced by the new
61st Division, offered stubborn resistance to the German I Corps, but the left flank of the corps was pushed back 7 km. The position of the Russian armies was threatening, on the night of August 13, the Russian armies continued to withdraw, but he was quickly discovered by the enemy. Already at 3 o'clock the Germans began the pursuit, introducing the 86th Infantry Division into battle again. The Germans advanced 18-20 km to the east until evening, and the I Corps - up to 25 km. The 1st and 2nd Armies retreated towards
Brest-Litovsk. In the Russian 1st Army, the 21st Army Corps could not withstand the German onslaught and retreated across the Narev River, followed by the 27th, 4th, 1st Siberian and 1st Cavalry Corps. Not hoping to stay on randomly busy lines. A. Litvinov ordered the army to withdraw on the night of August 15. On August 15, the corps of the center and left wing of the army of M. von Gallwitz reached the Myanka River, repelling Russian counterattacks and capturing 2,900 prisoners. On August 16, the Germans discovered the withdrawal of the Russian 12th and 1st Armies to
Białystok. Aerial reconnaissance showed that the outskirts of the city were fortifying, heavy artillery was delivered there. By evening, the troops of M. von Gallwitz reached the Narew River along the entire course. On August 17, the Russian 2nd, 1st and 12th Armies went on the offensive to push the Germans back from Białystok and Velsk. The strongest attacks were directed at the junction of the German 9th and 12th armies. The 2nd Austro-Hungarian Cavalry Division was driven back. In the sectors of other corps of the 12th and 8th Armies, the Russian offensive did not bring success, but the Germans was pressed to his trenches. From the decoded radiograms, the staff of Gallwitz received information that the Russian troops were occupying defensive positions. Gallwitz believed that on the line between the Narew and the Bug, the Russian armies would create a strong defense for long-term resistance. He admitted that the attempt to envelop the Russian armies failed due to insufficient pressure on the near flanks. On August 18, the Russian 1st, 2nd and 12th Armies withdrew to new positions, leaving strong rearguards against the junction of the 12th and 8th armies of the enemy until noon. The pursuit began at noon, the German troops marched more than 13 km. By the end of August 21, the troops of M. von Gallwitz reached the line east of Brest-Litovsk. Troops of the 9th Army took
Kleszczele. The quartermaster general of the staff of the army group P. von Hindenburg, Lieutenant Colonel M. Hoffman, announced a new task set by the Supreme Commander of All German Forces in the East: to reach the Riga-Grodno-Brest line. On August 23-25, in stubborn battles with the Russian rearguards of the 1st, 2nd and 4th Armies, the German troops advanced in the bend of the Narew and approached
Białowieża Forest from the west. On the night of August 26, the Russian troops retreated again, pursuing them, the German divisions occupied Białystok (37th division of the 8th Army). On the same day, the Germans occupied Brest-Litovsk, set on fire during the retreat. With the fall of Brest-Litovsk and Białystok, the Bug-Narew offensive came to an end. ==Outcome==