Thanksgiving is a time for rejoicing and healing, for celebrating our freedom. It couldn’t come at a better time this year then after such a fractious and polarizing election. But as Melanie Kirkpatrick points out in her new evocative and comprehensive history of the holiday, even Thanksgiving has been a source of controversy for centuries. 

There is a lack of consensus over where our Thanksgiving first originated, and there are other legitimate claims besides the Pilgrims at Plymouth Rock. Whether it was the Spanish colony of San Elizario, Texas in 1598 or the French protestants in Fort Caroline, Florida in 1564 or the Spanish colony at Palo Duro Canyon, Texas all the way back in 1541, in each case there was a religious theme and often a celebration of a successful harvest.

Survival wasn’t a given, making a ceremony to give thanks more important. The Pilgrims landed in Cape Cod in 1621 and many died during those first brutal winters. They hunted wild turkeys and fished for cod and bass. They didn’t celebrate their first day of thanksgiving until two years later. Connecticut was the first colony to establish it as an annual event in September 1639. 

After the Revolutionary War, there was controversy and a dispute over whether Thanksgiving should be a national holiday or whether it was really a subject for the states or the church. George Washington resolved the matter by issuing his very first presidential proclamation designating Thursday, November 26th 1789 as “a day of public thanksgiving and prayer.” According to Kirkpatrick, this proclamation was well heeded even though “it did not carry the force of law.”

The Civil War was marked by thanksgiving proclamations by both Presidents Jefferson Davis and Abraham Lincoln to celebrate military victories and inspire the troops, ending with the Battle of Gettysburg in August 1863.  Afterward Lincoln followed Washington’s example and once again set Thanksgiving Day for the last Thursday of November. In so doing he was transforming the holiday from military strategy back to something far more transcendent as he attempted to bring the country back together to heal. “It was a profoundly hopeful message,” Kirkpatrick writes, “Reminding the American people of the nation’s capacity for renewal.”

The controversies surrounding Thanksgiving continued into more modern times. When Franklin Roosevelt decided to move it up a week in 1939 to increase the length of shopping time until Christmas during the Great Depression, he unleashed a firestorm of protest.

Ultimately Thanksgiving represents progress and unity, often following a period of profound disparity. It is meaningful that since 1845 the holiday has followed Election Day, where we also celebrate our freedom. In 2016 we are currently experiencing protests and demonstrations following one of the most divisive and disturbing national elections in American history. There was a clear separation among voters and little acknowledgment of others’ point of view. The national blood pressure and heart rate rose precipitously, and everyone’s stress hormones were at an all time high.

But now is the time to heal our wounds. Conservatives and liberals need to be able to sit and break bread together at the same table. Thanksgiving is a very good time to offer charity to those who are homeless or can’t afford a meal. Those of us who feast do so because we can, (please go easy on the desserts and wine and potatoes eat plenty of green vegetables and salads).

We are a country of disparate ideas that emanate from many different backgrounds and cultures. We need to respect and honor each other and defend our right to free speech. We need to come together behind our new president, just as we have come together behind previous presidents, beginning with Washington.

Thanksgiving is the place to start, and Melanie Kirkpatrick has set the right tone. This is a day to overcome our differences in order to celebrate America. 

Dr. Marc Siegel, a practicing internist, joined FOX News Channel (FNC) as a contributor in 2008..