This article aims to clarify the attitude of the Italian Northern League (Lega Nord) toward the Catholic Church and Catholic faith, since its creation in 1991. The article examines the evolution of the party from the merger of the northern regionalist parties under the leadership of Umberto Bossi (1991–2012) until its current form and its reengineering by its new leader, Matteo Salvini, as a national(ist) League (Lega) aiming to win votes and mandates all over Italy and to become the dominant party of the Italian right. Be it under Bossi or Salvini, the Lega Nord/Lega has always opposed both the humanist teaching of the Catholic Church and mainstream Catholic social organizations, while pretending to defend the “Catholic identity” of the “North,” before turning to the entire country. Under Salvini’s leadership, the Lega joined forces with some rightist Catholic groups prone to complain about Pope Francis’s deemed treason of the Catholic identity, and so reinforced its conservative orientation. As I will show in this article, in the medium term, the enduring success of the Lega Nord/Lega illustrates the decline of mainstream Catholicism in Italy.