against the charge of being a proto-Nazi. Geyl's historical outlook Geyl was best known as a critic of the British historian Arnold J. Toynbee, who seemed to maintain that he had discovered "laws" of history that proved how civilisations rise and fall. Geyl often debated Toynbee both on the radio and in print. He accused Toynbee of selective use of evidence to support pre-conceived notions and of ignoring evidence that did not support his thesis. In addition, Geyl considered Toynbee's theory to be simplistic, ignoring the full complexity of the past; he regarded Toynbee's theory of "challenge and response" to explain historical change as too loose and a catch-all definition. Finally, Geyl was opposed to Toynbee's apparent claim that Western civilisation was in terminal decline. Geyl was noted for challenging the then-popular theory that the historical separation of the Dutch and the Flemings was a result of "natural" causes. Geyl claimed that there was a "Greater Netherlands" history and that the Dutch and Flemings only separated during the Eighty Years' War (better known as the Dutch Revolt in the English-speaking world) against Spain in the 16th century. Geyl argued that the revolt failed in the south not because of political, cultural or religious differences, but only because the geography in the north with its lakes, bogs and rivers favoured the rebels and the geography in the south with its flat plains favoured the Spanish Army. Had it not been for the accident of geography, Flanders would have been part of the Dutch Republic. Geyl expressed his ideas in a series of articles and in his main work, De Geschiedenis van de Nederlandse Stam (1930–1959, unfinished). In accordance with his historical ideas, Geyl actively supported the Flemish movement, though not favouring Dutch-Flemish irredentism. Geyl's work has been criticised for not taking into account the unifying force of administrative and economic developments after the separation and for sometimes drawing artificial boundaries based on language alone; on the other hand, it has been praised for its refreshing approach to the Dutch Revolt, which was in marked opposition to the then-current nationally oriented, almost finalistic view on Dutch and Belgian history as represented by P.J. Blok and Henri Pirenne. Geyl was also noted for arguing that the House of Orange and the Dutch people were often in conflict, especially during the 18th century. Geyl accused William IV of Orange of using the uprising of