2nd Mountain Brigade (2. Brygada Gorska) was a unit of the Polish Army, which took part in the Polish September Campaign. Commanded by Colonel Aleksander Stawarz, it was part of Operational Group "Jasło" of Army Karpaty. Its purpose was to defend a 80-kilometer section of Polish-Slovakian border, from Czorsztyn to the Beskid Mountain Pass. Facing the Poles to the south, in Slovakia, were two German Mountain Divisions and one Slovakian division, which would attack north, along valleys of the Dunajec and the Biała rivers.
In the morning of 1 September 1939, 2nd Mountain Brigade was attacked both by the Slovaks (in the area of Mniszek) and the Wehrmacht (in the area of Spisz). Slovak units did not succeed, but the Germans managed to capture such towns as Zakopane, Czorsztyn and Szczawnica. Thus, the Brigade was forced to retreat north, fighting continuously along the way.
In the morning of 5 September, units of the Brigade were located in Nowy Sącz. In the chaotic retreat, commanders did not cooperate with each other and chaos ensued. Soon afterwards, the Germans, taking advantage of the situation, captured Nowy Sącz, together with bridges, which Polish troops had not destroyed in time. The Brigade withdrew to Gorlice and on 8 September - to Krosno. When tired soldiers recuperated, German motorized troops suddenly entered the city, capturing most of PFC's and officers. Thus, the Brigade ceased to exist, its remnants withdrew towards Brzozów and Bircza, fighting several skirmishes with advancing Wehrmacht.