The autumn celebration in late 1621 that has become known as "The First Thanksgiving" was not known as such to the Pilgrims. The Pilgrims did recognize a celebration known as a "Thanksgiving", which was a solemn ceremony of praise and thanks to God for a congregation's good fortune. The first such Thanksgiving as the Pilgrims would have called it did not occur until 1623, in response to the good news of the arrival of addit...