As a Continental Reformed church, its doctrines and practices reflect a Calvinist theology, for which the Hungarian term is református (pronounced [ˈrɛformaːtuʃ]).

The northwest came under Habsburg rule; the eastern part of the kingdom and Transylvania (vassal state) came under the Ottoman Empire.

Finally, the 1867 establishment of the Austro-Hungarian Dual Monarchy gave free way for the legal emancipation of Hungarian Protestants.

The internal hierarchy and the synodal-presbyterian system of the Reformed Church remains nearly unchanged from that time.

After World War I, the Treaty of Trianon in 1920 greatly altered the Hungarian Reformed Church.

It made two two-thirds of the Hungarian people and a large number of Reformed Synod's and congregations suddenly within foreign countries.

After the confiscation of church lands, schools and institutions, on October 7, 1948, the General Secretary of the Communist Party, Mátyás Rákosi, forced the Reformed Church to sign an agreement that brought all the denomination's work and personnel under the control of the secret police, the ÁVH and the MIA III, and of the ruling Communist Party of Hungary.

The RCH (as a member of the worldwide Reformed Church family) is constructed in a representative way from below, from the congregational level.