For most of 1919, the 9th Division's regiments were dispersed across the regions of Podlachia, Polesie and Volhynia, with one battalion sent to Dąbrowa Basin.

It was formed on June 12 of that year, in Polesia, out of units of Operational Group Polesie, commanded by General Antoni Listowski.

A commemorative parade took place in Brześć Litewski on February 13, and soon afterwards, the 34th Regiment was transported by rail to Kobryn to defend the line of the Mukhavets.

Divided into three groups, the Poles captured Drahichyn and Janów Poleski, and then advanced along the rail line from Brześć to Pinsk.

Finally, on March 5, the Poles seized Pinsk and then headed towards Luniniec, but failed to capture this important rail junction.

On July 1, 1919, divisions of the Polish Lithuanian-Belarusian Front began an offensive to capture Minsk and to reach the line of the Berezina river.

The 9th Division protected the right flank of the Polish front, seizing the important rail junction of Luniniec on July 10.

During the fighting in the Kyiv area, the Polesie Group of the Polish Army (General Władysław Sikorski) was ordered to attack and reach the line of the Dnieper near its confluence with the Prypec.

In early June 1920, the Soviet 12th Army crossed the Dnieper, threatening Polish forces in Kyiv with encirclement.

In late July, two regiments of the division were transported to the area of Grodno, fighting the Cavalry Army of Hayk Bzhishkyan.

As part of the Fifth Army, it was tasked with protecting the left wing of the Polish Northern Front until the planned Wieprz river offensive.

In December 1922, after the election in which Gabriel Narutowicz became the President of Poland, the division sent two battalions to Warsaw to prevent street fighting.

Commandant of the Siedlce garrison, Colonel Franciszek Sikorski, sent on May 12, 1926, his soldiers to guard strategic locations in the town, including its important rail junction.

In the evening, soldiers of the 9th Division fought on the streets of Warsaw, and after the coup, officers of the unit were decorated by Piłsudski for their loyalty.

Since the 27th Division did not arrive on time, General Władysław Bortnowski ordered both units to attack simultaneously, with the support of Czersk Operational Group.

Thus, the Polish attack was set to begin on the morning of September 3, and the objective was to push the Germans back behind the Brda.