The original copy of the 1849 constitution declaring a Roman Republic is on display at the Capitoline museums on the occasion of its 162th-anniversary. On loan from the Augusta library in Perugia, the volume can be viewed in the Sala dei Capitani until 20 February 2011.

Unique among the constitutions enacted in Italy during the revolutionary movements that swept Europe during 1848-1849, the Roman constitution was the only one debated and approved by an elected constituent assembly, and its legislators appear to have drafted it with a future united Italy in mind. As well as guaranteeing a secular state, the Roman Republic became only the second state in the world to abolish the death penalty, after the Grand Duchy of Tuscany.

The events that brought about the constitution came on 24 November 1848 when Pope Pius XI fled to Gaeta south of Rome in the wake of the riots which followed the assassination of prime minister Pellegrino Rossi. On 9 February the following year a decree was passed declaring the Roman Republic, initially led by the triumvirate of Giuseppe Mazzini, Aurelio Saffi and Carlo Armellini, while the city