When the Mayflower pilgrims landed at Plymouth Rock and found vacant Indian settlements, recently emptied from epidemics that killed off entire villages, their view of it was that their God saw fit to kill Indians on their behalf, making room for them. It was certainly a convenient perspective, relieving them (and their English brethren) of any responsibility for the deaths of tens of thousands of other human beings due to the germs they brought over with them from the filthy conditions they were accustomed to living with back in the old country. It wasn't as if they didn't know by then that it was illnesses brought by them that killed the Indians. We know for sure that by 1763 those good Christian men were using biological warfare to further clear the land when Lord Jeffry Amherst sent smallpox infested blankets to the Delaware and Shawnee.
Be that as it may, by 1620 the beleaguered Wampanoag and their leader Massasoit whom the pilgrims encountered at Plymouth Rock were already on their way out. But contrary to popular opinion they did not become extinct; those that remained--believing that their God had abandoned them--adopted the religion of the invaders, eventually blending in with them through time. But the descendants of the original Wampanoag, having always known who they are, still exist. Their culture has taken a beating and much of their work revolves around reviving what they can.
There is a saying that when a language dies, a culture dies. If this is true, then conversely when a language is revived, it stands to reason that the culture is revived. The Wampanoag language was deemed to be extinct at least 100 years ago. But if there was only one good thing that came from the Christian missionaries it is that much of the Wampanoag language was preserved in writing, enabling today's Wampanoag descendants to reconstruct their language and thus their cultural heritage.