OK, so we celebrate that the Pilgrims landed on Plymouth Rock. They were "driven out" because of their heretical Religious Beliefs (which would be considered heretical by most Christians today - indeed, most of Americans today).
These were just average people who had been told of a "promised land", and of those who did not die on the journey most of the survivors died during the first winter. Because they weren't prepared.
So, the Native people - the Wampanoag - took pity on them and taught them how to plant and how not to just survive, but to thrive!
Then, rather than thank the Wampanoag who basically saved their lives, they thanked God for sending the heathen Wampanoag to save them. They invited the Wampanoag to their feast, who graciously accepted the invitation.
And then, the Pilgrims killed the Wampanoag - who took pity on them and saved their lives - in order to take their land.
Have I got that right? Is that what we're celebrating?