Europeans-borne plague killed-off most Indians in New England before the Pilgrims got there

Did you know that a plague borne by Europeans killed off most native Americans in Massachusetts before the Pilgrims got there? "British fishermen had been fishing off Massachusetts for decades before the Pilgrims landed," James W. Loewen points out. They transmitted to the Native Americans probably what was bubonic plague (possibly small pox or the flu), and

within three years this plague wiped out between 90% and 96% of the inhabitants of southern New England. The Indian societies lay devastated. Only "the twentieth person is scarce left alive," wrote British eyewitness Robert Cushman, describing a death rate unknown in all previous human experience.

Smallpox epidemics followed.

These epidemics constituted perhaps the most important single geopolitical event of the first third of the 1600s, anywhere on the planet. They meant that the British would face no real Indian challenge for their first fifty years in America. Indeed, the plague helped cause the legendary warm reception Plymouth enjoyed in its first formative years from the Wampanoags. Massasoit needed to ally with the Pilgrims because the plague had so weakened his villages that he feared the Narragansetts to the west.

Charles Mann, author of 1491, summarizes it thus:

By the time [of] the Mayflower, Europeans had been visiting New England for more than a hundred years.... New England, [they] saw, was thickly settled and well defended. In 1605 and 1606 Samuel de Champlain visited Cape Cod, hoping to establish a French base. He abandoned the idea. Too many people already lived there. A year later Sir Ferdinando Gorges—British despite his name—tried to establish an English community in southern Maine. It had more founders than Plymouth and seems to have been better organized. Confronted by numerous well-armed local Indians, the settlers abandoned the project within months. The Indians at Plymouth would surely have been an equal obstacle to [the Pilgrims'] ramshackle expedition had disease not intervened.