Austrian troops occupied Piacenza until, in 1860, a plebiscite marked the entrance of the city into the Kingdom of Sardinia. 37,089 voters out of 37,585 voted for the annexation. Piacenza was therefore declared "Primogenita dell'Unità di Italia" ("First-born of the Unification of Italy") by the monarch. The Piacentini enrolled en masse in the Giuseppe Garibaldi's army in the Expedition of the Thousand.