The war began at Fort Detroit under the leadership of Pontiac and quickly spread throughout the region. Eight British forts were taken; others, including Fort Detroit and Fort Pitt, were unsuccessfully besieged. Francis Parkman's "The Conspiracy of Pontiac" portrayed these attacks as a coordinated operation planned by Pontiac. Parkman's interpretation remains well known, but later historians argued there is no clear evidence the attacks were part of a master plan or overall "conspiracy." Rather than being planned in advance, modern scholars believe the uprising spread as word of Pontiac's actions at Detroit traveled throughout the "pays d'en haut", inspiring discontented Indians to join the revolt. The attacks on British forts were not simultaneous: most Ohio Indians did not enter the war until nearly a month after Pontiac began the siege at Detroit.