Pospolite ruszenie (also referred to with the French term levée en masse), is an ancient Polish term to describe the mobilisation of armed forces, especially in the times of the Polish-Lithuanian Commonwealth. This term is now considered archaic.

Before the 13th century it was the main backbone of the army. After that period, only landowners were mobilised. These included knights — who later transformed into nobles (szlachta) — as well as wojts and soltys .

Pospolite ruszenie units were usually organised on voivodship basis and varied in quality. Szlachta from regions like Kresy, where combat was common, created farily competent units, while those from peaceful regions of the Commonwealth lacked battle experience and training and often were substandard compared to wojsko kwarciane or mercenaries.

Szlachta usually created cavalry units, and their favoured weapon was szabla (kind of saber).

The privileges granted by kings to the szlachta have consequently limited the right of kings to call for pospolite ruszenie, especially for actions outside the territory of Poland. The pospolite ruszenie was eventually outclassed by professional forces.

After 1794, pospolite ruszenie was considered to consist of all able males between 18 and 40 years of age. In 1806 by decree of Napoleon, the pospolite ruszenie in the Duchy of Warsaw served for a short period as the reserve force and recruitment pool for the regular army. During the November Uprising in 1831, the Sejm called for pospolite ruszenie from ages 17 to 50, but that plan was opposed by General Jan Zygmunt Skrzynecki .

In the Second Republic of Poland, the pospolite ruszenie was considered to consist of reserve soldiers from ages 40 to 50 and officers from ages 50 to 60. They had to participate in army exercises and serve in armed forces during times of war.