They never, ever called themselves “Pilgrims.” The “First Thanksgiving” in 1621 — actually a secular, three-day harvest festival held sometime between September 21 and November 11 — was the only Thanksgiving they ever celebrated. They dressed in earth-tones, not black and white, nor did they wear buckles on their shoes. They probably dined on wild turkey, venison, seafood, Indian cornmeal, stewed pumpkin, nuts and plums, but there was no ham, no mashed potatoes, no corn on the cob, pumpkin pie or cranberry sauce to be had. Thanksgiving didn’t become a national holiday until President Abraham Lincoln declared it so in 1863.