What Is Ultramontanism and Neo-Ultramontanism?

Ultramontanism refers to the theology that the Pope is the head of the Church, can bind the whole Church, and can teach infallibly. It stands in opposition to various forms of conciliarism which deny the Pope can act outside of a Church council.

Neo-ultramontanism essentially believed that the Pope is infallible in virtually every Papal teaching, not just in the limited circumstances of ex cathedra.