Abstract
This paper describes nationalism as a phenomenon that has become an integral part of Czech society in the 19th century and its manifestations. It describes the main motives Czech nationalist ideology created by T.
G. Masaryk.
It also described the political situation during the First World War and the circumstances of the independent Czechoslovak state and its share in breaking the Austro - Hungarian monarchy. The work deals with the problem of modernism in the Catholic Church, whose adherents later became the founder of the Church of Czechoslovakia.
Briefly describes the lives of the founders of the church and their relationship to nationalist political movements. The core of the work is the analysis of texts relating to the reform movement of the Czech Catholic clergy and the Czechoslovak church, from the period between 1906 - 1931, which is determined by the definition of nationalism seeks to assess its impact on the formation and other life Czechoslovak Church.