History.com is one of the best online sources for historical material.

For example:

In 1621, the Plymouth colonists and Wampanoag Indians shared an autumn harvest feast that is acknowledged today as one of the first Thanksgiving celebrations in the colonies. For more than two centuries, days of thanksgiving were celebrated by individual colonies and states. It wasn’t until 1863, in the midst of the Civil War, that President Abraham Lincoln proclaimed a national Thanksgiving Day to be held each November.

In September 1620, a small ship called the Mayflower left Plymouth, England, carrying 102 passengers—an assortment of religious separatists seeking a new home where they could freely practice their faith and other individuals lured by the promise of prosperity and land ownership in the New World. After a treacherous and uncomfortable crossing that lasted 66 days, they dropped anchor near the tip of Cape Cod, far north of their intended destination at the mouth of the Hudson River. One month later, the Mayflower crossed Massachusetts Bay, where the Pilgrims, as they are now commonly known, began the work of establishing a village at Plymouth.

Did You Know?: Lobster, seal and swans were on the Pilgrims’ menu. Turkey was not

Throughout that first brutal winter, most of the colonists remained on board the ship, where they suffered from exposure, scurvy and outbreaks of contagious disease. Only half of the Mayflower’s original passengers and crew lived to see their first New England spring. In March, the remaining settlers moved ashore, where they received an astonishing visit from an Abenaki Indian who greeted them in English. Several days later, he returned with another Native American, Squanto, a member of the Pawtuxet tribe who had been kidnapped by an English sea captain and sold into slavery before escaping to London and returning to his homeland on an exploratory expedition.

Squanto taught the Pilgrims, weakened by malnutrition and illness, how to cultivate corn, extract sap from maple trees, catch fish in the rivers and avoid poisonous plants. He also helped the settlers forge an alliance with the Wampanoag, a local tribe, which would endure for more than 50 years and tragically remains one of the sole examples of harmony between European colonists and Native Americans.

To check out text and a video in order to learn more about the first Thanksgiving, please click here.

Alas, this will not be a happy Thanksgiving for many people.  Please remember them and their loved ones in your thoughts and, if appropriate, in your prayers.