In 1451 Frederick V of Styria, elected King Frederick III of Germany in 1440, began his march on Rome, where, on 18 March 1452, he became the first Habsburg, and the last German king, to be crowned emperor by the pope in Rome, as tradition prescribed. With Frederick III began the Habsburg monopoly on imperial office until 1806 (excepting 1740–5), and the dynastic policies that were to bring his successors to the brink of universal monarchy. Yet Frederick III undertook his impressive procession to the imperial title in near bankruptcy and with little territory of his own. He could not pay for the march's expenses (the pope paid), and while he was proceeding to Rome the Austrian estates were in virtual rebellion, demanding the return of their rightful ruler, Ladislaw, Frederick's cousin and ward, whom Frederick had taken to Rome with him.

The rise of the Habsburgs to world power thus began with a claim to imperial and hence divine sanction quite at variance with modern notions of political reality. Over three centuries, from Frederick's becoming family head in 1440 to the accession of Maria Theresa in 1740, the Habsburgs sought to realize their divine right to rule, and not only to rule their own patrimony, but to preside as God's chosen dynasty over the entire civilized (Christian) world.