On the 30th of November 1808 the famous charge of Somosierra took place, which cost three regimental officiers their lives (a fourth one, the captain Dziewanowski, passed away due to his injuries a few days later).

As the approach to Madrid was blocked by 7,800 Spaniards armed with 16 cannons in four batteries on the Somosierra heights, Napoleon ordered his Poles to force the passage.

Lieutenant Niegolewski, the last able-bodied officer, led the end of the charge: with about thirty survivors, he reached the last battery, saw his horse killed under him and, in the fall, broke a leg.

Napoleon then launched a second charge with the three remaining Polish squadrons under Tomasz Łubieński, followed by the Guards' mounted chasseurs.

Still alive, very seriously wounded, Lieutenant Niegolewski was still lying on the ground under his horse when Marshal Bessières approached him and said, "young man, the Emperor has seen the beautiful charge of the Light Cavalry; he will know how to appreciate your bravery."

When he arrived on the plateau, the Emperor immediately awarded him the Cross of the Legion of Honor, taking it off his own uniform, and making him the first officer of his regiment to receive it.

In September, he was discharged from active service for health reasons and returned to the Greater Poland region.

In the following years, he was one of the most active activists in Greater Poland, defending the Polish language in the public life of the Grand Duchy of Poznań in the provincial parliament, where he was an elected member.

He was a deputy of the chivalry of the Buk and Oborniki powiats (counties) in the provincial parliament of the Grand Duchy in 1827 and 1830 before the uprising.