Sidney Costantino, Baron Sonnino was an Italian statesman, 19th prime minister of Italy and twice served briefly as one, in 1906 and again from 1909 to 1910. He also was the Italian minister of Foreign Affairs during the First World War, representing Italy at the 1919 Paris Peace Conference.

The Banca Romana scandal surfaced in January 1893 in Italy over the bankruptcy of the Banca Romana, one of the six national banks authorised at the time to issue currency. The scandal was the first of many Italian corruption scandals, and discredited both ministers and parliamentarians, in particular those of the Historical Left and was comparable to the Panama Canal Scandal that was shaking France at the time, threatening the constitutional order. The crisis prompted a new banking law, tarnished the prestige of the Prime Ministers Francesco Crispi and Giovanni Giolitti and prompted the collapse of the latter's government in November 1893. The scandal led also to the creation of one central bank, the Bank of Italy.