Thanksgiving was first observed when the Pilgrims first settled in the New World. In 1789 George Washington issued a proclamation and America celebrated its first Day of Thanksgiving but it was not a National Holiday. This didn't happen until 1863 when Abraham Lincoln set aside the last Thursday of November as a national Day of Thanksgiving. In 1941, Congress established it as the fourth Thursday in November (sometimes there are five). Canada has a harvest Thanksgiving on the second Monday in October.
I wish you all a very "thankful" Thanksgiving!
Psalms 140:1 - "Surely the righteous shall give thanks unto thy name: the upright shall dwell in thy presence."