The Kingdom of Italy (Italian: Regno d'Italia) was a state that existed from 1861, when Victor Emmanuel II of Sardinia was proclaimed King of Italy, until 1946, when civil discontent led to an institutional referendum to abandon the monarchy and form the modern Italian Republic. The state resulted from a decades-long process, the Risorgimento, of consolidating the different states of the Italian Peninsula into a single state. That process was influenced by the Savoy-led Kingdom of Sardinia, which can be considered Italy's legal predecessor state.

Kingdom of Italy - Wikipedia