Why is Thanksgiving observed on the last Thursday in November?
Sarah Josepha Hale, a 74-year-old magazine editor, wrote a letter to Lincoln on September 28, 1863, urging him to have the "day of our annual Thanksgiving made a National and fixed Union Festival." She stated that only the chief executive had the power to make the holiday, “permanently, an American custom and institution.”
Prior to this, each state scheduled its own Thanksgiving holiday at different times. President Lincoln responded to Mrs. Hale's request immediately.