Thanksgiving was officially established as a national holiday in the United States by President Abraham Lincoln in 1863, during the Civil War. He declared it a day of “Thanksgiving and Praise” to be celebrated on the last Thursday of November. The holiday itself, however, traces back to the early 1600s, when English Pilgrims and the Wampanoag people shared a harvest feast in 1621 in Plymouth, Massachusetts. Today, Thanksgiving is celebrated on the fourth Thursday of November and is marked by family gatherings, feasts, and expressions of gratitude.