3 The general duty of Catholics to preserve the integrity of religion in their country in all vicissitudes, and to do so in a spirit of unity, becomes a serious obligation during times of treacherous hostilities to Christian institutions. Indeed, not only is the interest of the highest good of all at stake, namely the eternal salvation of mankind, but also the protection and preservation of the very things that in civil society contribute most importantly to true peace and happiness. This was clearly the conviction of those eminent men, brilliant examples of moral fortitude, who were ready to sacrifice not only all their possessions, but their very lives for the sake of religion and the Church. Among these heroes, your Hungary has its share down the long course of your history. The fact that you have persevered steadfastly in the Catholic faith is the result of the firm determination of your people. They certainly understood perfectly that when religion is at stake, so is the glory of the name and the existence itself of their nation.
Source: Constanti Hungarorum (Vatican.va)