Lateran Treaty

The Lateran Treaty made the Vatican an independent state for the first time since Giuseppe Garibaldi's lifetime when it was annexed into a unified Italy to fulfill the anti-Catholic Garibaldi's wishes for Rome to be the capital of Italy. The Vatican is where the head of the Catholic Church lives.
For a dictator like Mussolini, this was a rare good deed. In fact, in order for the Vatican to recognise Italy, it had to be done. When the treaty was signed:

• The Vatican was recognised as an independent state.
• Mussolini agreed to pay 750 million lire (Old Italian currency) to the Vatican to compensate for the loss of the Papal States in the 19th century
• Catholicism became the official religion of the state.
• For the first time since the unification of Italy in 1870, the Catholic Church agreed to recognise the authority of the Italian state.