From its beginning, Christianity had a place where it turned to its God and celebrated the Eucharist. Such places, which were remodelled or built for this purpose, are called sacred architecture. Sacred architecture has always included various forms of art that served to design and decorate space for the glory of God, which is why the role of architecture in the church building is immeasurable. Throughout Christian history, church building has been shaped by different visions of church building, guided and inspired by different theological- liturgical emphases. These emphases have produced different styles throughout the history that build on each other. All ancient styles of building built church buildings according to certain principles and laws. Based on Vitruvius' requirements for building utilitas, firmitas, and venustas, the principles of sanctity, beauty, and transcendence were evident, as were the laws of iconography, verticality, and timelessness. This succession of styles that emerged from the preceding ones can be traced back to the emergence of Modernism. Modernism, with its philosophy of observing buildings and a new concept of space, also influenced church construction in the 1920s. The architects who built church buildings at that time were already trained in the spirit of Modernism and brought its postulates of functionality, abandonment of decoration, and creation of a non-hierarchical space to sacred space. Although the guidelines of the Council of Trent are still valid, postulates of Modernism which are mostly spurred by the internal movements within the church, reject the remaining guidelines, except for the orientation of the altar versus oriente. These movements have given rise to liturgical movements that, inspired by Pope Pius X's encyclical Tra le sollecitudini, are redefining the liturgical space with their vision of the liturgy. In their small communities, they turn the altar toward the people in the celebration of Mass, in order to reach a larger community. In such way, the celebration of Mass challenges the previous liturgical space defined by the guidelines of St. Karel Boromjeski adopted at the Council of Trent. In churches that are built in the spirit of modernism, the altar continues to be placed according to the existing guidelines, but the church buildings are constructed according to new concepts. The new concepts emphasize functionality, non-hierarchy and complete reductionism. According to these concepts, modern church buildings remain free of any decorative elements, while simple straight surfaces prevail. The concepts are also visible in the liturgical space, which is also devoid of decorative elements, as well as the hierarchy of space that existed before. The sanctuary and the nave of the liturgical space are now under the same roof, as the triumphal arches that separated them have disappeared. Throughout the Christian world, church buildings characterized by a new spirit that rejects the earlier elongated building type and emphasizes the central type are emerging. The Church responded to this development in sacred architecture at the Second Vatican Council by adopting what had already become practice. Liturgical space is redefined, and the practice of turning the altar toward the people, which had been tacitly passed over until then, becomes a recommendation in liturgical documents. Following this recommendation, church buildings after the Second Vatican Council are built only according to the already established concept of liturgical space, which dates back to modern times. Since the Second Vatican Council emphasizes ecclesiasticism, and the liturgical space is designed to include the gathered congregation as much as possible, this is made possible through central and hall construction. In addition to the changes in liturgical space, the external appearance of church buildings has also changed, as they now more closely resemble general interest buildings such as health centers, sports halls, etc. Croatia is not behind the rest of the world when it comes to sacral construction. At the beginning of modernism, building was done in the same way as in the rest of Europe, because Croatian architects belong to the same architectural scene and have received their education at the same universities and schools. In the interwar period, modernism prevailed in church building, ornamentation was reduced and materials such as concrete and steel were used. A longitudinal type with a cross base can still be seen in the ground plans. Representative church buildings in Zagreb from this period are the Church of St. Blaž, the Chapel on Sljeme, the Church of St. Marko Križevčanin, the Church of St. Antun and the Church of Our Lady of Lourdes, which unfortunately was not completed according to the original plans. Besides Zagreb, the Church of Our Lady of Health in Split and the Church of St. Roumald and All Saints in Rijeka are also worth mentioning. The well-known Croatian architects V. Kovačić, J. Denzler and M. Haberle were involved in the construction of these churches. In Split, L. Horvat worked on the project and in Rijeka, which was then under Italian administration, B. Angheben. After the Second World War almost nothing was built in Croatia, only in Podgora, after the earthquake during the Second Vatican Council, the Church of the Assumption was built by the architect A. Rožić. The Second Vatican Council introduced new guidelines for the construction of church buildings, but without abolishing the previous guidelines. In Croatia, which was under communist rule at the time, very little was built to meet the need because of the government's attitude toward the Church. In the 1970s and 1980s, building permits were issued in only a few places, and what was built was already in the spirit of late modernism and postmodernism, but with all the postulates that modernism brought to sacred building. This was the situation until the end of the Homeland War, when the construction of church buildings expanded. Churches were built in the spirit of modern architecture, which had already developed in the contemporary, but with all the postulates of modernism.