The Holiday from Wikipedia:
Thanksgiving proclamations were made mostly by church leaders in New England up until 1682, and then by both state and church leaders until after the American Revolution. During the revolutionary period, political influences affected the issuance of Thanksgiving proclamations. Various proclamations were made by royal governors, John Hancock, General George Washington, and the Continental Congress, each giving thanks to God for events favorable to their causes. As President of the United States, George Washington proclaimed the first nation-wide thanksgiving celebration in America marking November 26, 1789, "as a day of public thanksgiving and prayer to be observed by acknowledging with grateful hearts the many and signal favours of Almighty God".
In modern times the President of the United States, in addition to issuing a proclamation, will "pardon" a turkey, which spares the bird's life and ensures that it will spend the duration of its life roaming freely on farmland.
more here.... http://en.wikipedia.org/wiki/Thanksgiving
"WOD" = "Workout Of the Day".