George Goudie Chisholm, Philip Lake, Arthur Hassall, Walter Alison Phillips, and Donald Mackenzie Wallace, 1911 Encyclopædia Britannica, Volume 9… (1911)
“ It is, indeed, impossible to exaggerate the influence of the Roman Church upon the development of Europe at this period. The popes, in fact, represented Europe in a sense that could not be predicated of the emperors; the terror of their spiritual power, their vast wealth derived from the tribute of all the West, their unique experience of international affairs, and—in the case of the great popes of this epoch—the superiority of their minds and characters, made them not only the spiritual rulers of Europe, but the effective centres of whatever political unity it possessed. ”
