Mariavitism first emerged from the religious inspiration of Polish noblewoman and nun Feliksa Kozłowska (1862–1921) living in the Russian Partition of Poland in the late 19th-century.

A young Catholic priest from a modest background, Jan Maria Michał Kowalski (1871–1942), became convinced by Kozłowska's revelations and adopted her vision as his own project by her side.

Their content was gathered in a volume entitled Dzieło Wielkiego Miłosierdzia (The Work of Great Mercy), published by the Marinate Press in 1922.

Observing the spread of "Mariavitism" across their ecclesiastical territory, Polish Catholic bishops were alarmed by the threat the movement posed to their apostolic authority and teachings and reported it to the Vatican probably in the late 1890s.

[3] From 1906 the newly independent denomination continued its development, in no small measure due to donations and support from the faithful.

Kozlowska's own acquisition of 400 hectares of land in Płock, enabled not only the construction of a cathedral, completed "in-house" by two professionally qualified architects and engineers (Maria Mateusz Szymanowski [pl] and Maria Bartłomiej Przysiecki [pl]) who brought into the church considerable personal 'dowries' for the construction in Płock, of the Sanctuary of Mercy and Charity(1914) with adjoining monastic buildings,[4] but the development of revenue raising enterprises, such as educational facilities, a printing press, bakery and animal breeding.

[5] In turn, Kowalski went on to consecrate: Fatôme (France), Feldman, Gołębiowski, Próchniewiski, Rostoworowski, Siedlecki, and his own wife, Maria Izabela Wiłucka-Kowalska.

[8] The church struggled to maintain its reputation and standing during the Second Polish Republic in newly independent and sovereign Poland.

[9] Throughout its early tribulations with the Rome authorities, the church was led by Kozłowska's lieutenant, the catholic priest, later excommunicated, Michał Kowalski until 1935.

Among these were the introduction of married clergy, the subsequent birth of 'mystical children' separated from their parents for early rearing, the ordination of women, the establishment of a "priesthood of the faithful" and not least, Kowalski's own sexually predatory and abusive behaviour towards young nuns.

The dissident majority became known as the "Old Catholic Church of the Mariavites", which, after 1935, was led by bishop Maria Filip Feldman [pl] and remained based in the city of Płock.

The denomination confirmed all the decisions of Kowalski and introduced a public cult of Kozłowska, the Mateczka, the Spouse of Christ and new Redemptrix of the world.