The Italian Democratic Socialist Party, also known as Italian Social Democratic Party, was a social-democratic political party in Italy. The longest serving partner in government for Christian Democracy, the PSDI was an important force in Italian politics, before the 1990s decline in votes and members. The party's founder and longstanding leader was Giuseppe Saragat, who served as President of the Italian Republic from 1964 to 1971. Compared to the like-minded Italian Socialist Party on the centre-left, it was more centrist, but it identified with the centre-left.

Silvio Berlusconi was an Italian media tycoon and politician who served as the prime minister of Italy in four governments from 1994 to 1995, 2001 to 2006 and 2008 to 2011. He was a member of the Chamber of Deputies from 1994 to 2013; a member of the Senate of the Republic from 2022 until his death in 2023, and previously from March to November 2013; and a member of the European Parliament (MEP) from 2019 to 2022, and previously from 1999 to 2001. With a net worth of US$6.8 billion as of June 2023, Berlusconi was the third-wealthiest person in Italy at the time of his death.