Carroll Quigley

American historian at Georgetown who wrote The Evolution of Civilizations and Tragedy and Hope — the latter an account of the Anglo-American financial network's role in 20th century history — who was Bill Clinton's mentor at Georgetown and became a conspiracy theory touchstone for his descriptions of elite networks.

Developed a sophisticated civilizational model in which civilizations follow a deterministic life cycle (mixture → gestation → expansion → conflict → universal empire → decay → invasion) — and Tragedy and Hope's detailed documentation of the Anglo-American establishment's financial and political network (the Round Table) provided both serious history and conspiracy theory source material.