Southern Italy (Italian: Sud Italia or Italia meridionale) also known as Meridione or Mezzogiorno (Italian pronunciation: [mddzodorno]), is a macroregion of the Italian Republic consisting of its southern half.

Southern Italy covers the historical and cultural region that was once politically under the administration of the former Kingdoms of Naples and Sicily, and which later shared a common organization into Italy's largest pre-unitarian state, the Kingdom of the Two Sicilies.The island of Sardinia, which had neither been part of said region nor of the aforementioned states and had once been under the rule of the Alpine House of Savoy that would eventually annex the Bourbon Kingdom altogether, is nonetheless often subsumed into the Mezzogiorno.The Italian National Institute of Statistics (ISTAT) employs the term "South Italy" (Italia meridionale or also just Sud) to identify one of the five statistical regions in its reportings without Sicily and Sardinia, which form a distinct statistical region denominated "Insular Italy" (Italia insulare or simply Isole). These same subdivisions are at the bottom of the Italian First level NUTS of the European Union and the Italian constituencies for the European Parliament.

The 1908 Messina earthquake (also known as the 1908 Messina and Reggio earthquake) occurred on 28 December in Sicily and Calabria, southern Italy with a moment magnitude of 7.1 and a maximum Mercalli intensity of XI (Extreme). The epicentre was in the Strait of Messina which separates Sicily from the Italian mainland. The cities of Messina and Reggio Calabria were almost completely destroyed and between 75,000 and 82,000 lives were lost. It was the most destructive earthquake ever to strike Europe.