Well, the middle one admits the feast was secular . . .
. . and that the "day of thanksgiving" a couple years later definitely did not include a feast.
According to the Smithsonian article the only actual record of the first one was a complaint by one of the leaders about the rowdiness and amount of beer and supplies consumed, and mention that Indians wandered in and were sent out to get deer.
Most commentators are reluctant to be as brutal about it as Smithsonian Magazine was.
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