To achieve these goals, the Church supported clerical political parties, confronting them to other confessions, primarily to the Serbian Orthodox Church, by publicly preaching hatred against the Orthodox population and advocating Croatian and Slovene separatism and intolerance against others.
Josip Juraj Strossmayer's ideas, of which the most important one was - serving God equals to serving people, created close relations between Croats and Serbs by introducing the Old Slavonic language as the liturgy language of the Roman Catholic Church in the Balkans - were aggressively suppressed by the Roman Catholic clergy in Croatia and Slovenia. The clergy put the Roman Curia in between the God and the people, demanding from the Roman Catholics ultimate obedience to the Roman Curia and unconditional love of the Roman Pope. The clergy remaining faithful to the Strossmayer was marginalized, with the most ardent supporters excommunicated by the Zagreb archbishop.
Nevertheless, Strossmayer was embraced as a great Roman Catholic bishop by the same clergy - but his teaching was distorted or not mentioned ever. The same destiny faced Franjo Rački, Ante Trumbić, and Stjepan Radić - three Croatian politicians advocating actively and fighting for the Yugoslavism - as a common denominator of togetherness and life among the Slavic people of the kingdom of Yugoslavia. The Trumbić and Radić's struggle against centralism was interpreted as the Croatian and Slovene separatism support.
Novak demonstrated that even the anti-Croatian activities in the Italian Croatian and Slovene lands (as compensation for their aid in World War I) were not counteracted by the Croatian and Slovene Roman Catholic clergy in Yugoslavia. Expulsion of the Croatian and Slovene clergy from these lands and their replacement by the Italians was received with silence and accepted without resistance or protest among their Catholic brethren in Yugoslavia.
Ante Pavelić's political activities in the Kingdom of Yugoslavia, the Ustashe terrorism, and the embracement of fascism were all supported by the Roman Catholic clergy. Pavelić's nationalism identified Roman Catholicism to the Croatdom, which was actively supported and interpreted by the clergy.
The second part of this book is about the beginning of the Independent State of Croatia, the active support of the Roman Catholic clergy to this state, and their involvement and support in the extermination and/or forceful conversion of the Serbs and extermination of the Jews and the Roma people. The book is full of testimonies and documents showing the active involvements of the Catholic clergy in supporting, organizing, and executing extermination of Serbs, Jews, and Roma people of the Kingdom of Yugoslavia. One of the most bizarre events described was that Roman Catholic priests in the Jasenovac concentration camp working every day on the most gruesome ways to kill the camp inmates, while they went to chapel regularly each day to pray to God.
At the end of World War II, the Catholic clergy defended themselves, claiming their opposition to forceful conversion and extermination in some letters and instructions directed to the priesthood. The book notes that these letters and directions were not public and not respected or followed. In fact, an article from "Novi list"' argued that a Jew could not be save by converting to the Roman Catholicism.
Archbishop Aloysius Stepinac is portrayed in this book as an ardent Roman Catholic crusader who publicly endorsed the establishment of the Independent State of Croatia, acknowledged the Ustashe as Croatian patriots, defended her before the Roman Pope and was responsible for the racist attitude and behavior of his clergy.
This edition, except from being an English language translation of the 1948 edition, contains two new chapters - "XIV. Ecclesia militants at war with the ideology of Tyrš", and "XV. Libellus accusations", both omitted in the original version under the pressure of Josip Broz Tito's OZNA chief Maks Baće.
Chapter XIV is about the Sokol ("Falcon") Society, founded in Prague in 1862 by Jindřich Fügner and Miroslav Tyrš. The goal of the Sokol Society was to revive and enhance the national awareness and promote mental and physical health of the Czech people through sports and moral education. The idea soon gained a pan-Slavic character, and Sokol organizations were later established in Croatia, Slovenia, Serbia, Bulgaria, Poland, and Russia. The Sokol movement had full support from Strossmayer, then Bishop of Đakovo. After the dissolution of Austria-Hungary and the establishment of the Kingdom of Serbs, Croats, and Slovenes in 1918, and under the leadership of Lazar Car, Croatian Sokol societies were united with Serbian and Slovenian Sokol clubs into a large Sokol Alliance on 15 June 1919.
The separatism-prone Croatian clergy forced Croatian Sokols to leave the "Yugoslav Sokol Alliance" in 1919–20, fueling internal conflicts within the Alliance on political grounds. At the same time, high Catholic clergy established the Orlovi ("Eagles") clerical organization with the aim of taking youths away from the Alliance. The Croatian Catholic Church rejected the pan-Slavic idea of bringing together Catholic, Orthodox, and Muslim believers under the motto that ""a brother is dear regardless of his faith"". The two Catholic organizations, Orlovi ("Eagles") and Katolička Akcija ("Catholic Action") were a main base of this resistance to the idea of Yugoslavism, brotherhood and religious tolerance. The Catholic Church's resistance to this idea of pan-Slavism led the Polish Sokols to abstain from the international "All Sokol Rally" held in Prague in 1926.
Chapter XV, titled "Libellus Accusations", is about a few Croatian clergymen who were followers of Strossmayer's idea (namely, that to serve people means to serve God). The most prominent among them was Frano Ivanišević, a national fighter and promoter of Old Slavonic Church language as the language of liturgy in the Croatian Catholic Church. He demonstrated that a Catholic priest serving his people would not be against his Church and faith.
Among scholars-historians this book is accepted as a serious academic reference and as such - cited and referenced a great number of times . That way the book became a reference book in the libraries of many universities around the globe .
The earliest surveys of this book are the ones of Russian S. Troicky (as of the 1949 year - see the link) and of Swede O. Neumann. Neumann stressed three things particular to this book: the role of V. Novak in spreading and defending the idea of Yugoslavism, abundance of the documentation used to support the book content, and that ""Some passages have been written by a scholar in a dignified academic gown, in other parts of the book the author assumes the role of public prosecutor."" The abridged edition of this book published in 1960 is reviewed in the Istorijski glasnik and the same review echoed in the Historical abstracts.
A number of short notes about this book can be found - scattered in the works related to this period of history. Some are neutral and some rejective and disapproving.
The most recent, 2011 English language edition, was published in two volumes, and includes two chapters which had been excluded from all earlier editions of this book, which, according to Serbian historian Vasilije Krestić, were censored upon the request of two Croatian communist leaders, Vladimir Bakarić and Maks Baće. As reported by the Serbian daily "Politika", the publication of the English language edition was financed by a schoolmate of Milorad Ekmečić; Ekmečić wrote the foreword to the edition. According to the same article, the publication of the English translation was coincided with the Croatia's lawsuit against Serbia in front of the International Court of Justice, so that "the world would be informed about Ustashe crimes against Serbs during the Second World War".