For many Americans, Thanksgiving is a day of celebration – a holiday where you can get together with family, eat good food and be merry. It’s become such an institution, it’s often easy to forget its dark past.

While there are different accounts of the origins of Thanksgiving, the most common tale is of the pilgrims – the colonial settlers of America – breaking bread with the Wampanoag Nation (a collection of Native American tribes) on November 25 in the 1620s.

However, peace didn’t last long. In 1970 Wampanoag leader Frank James was asked to do a speech for Thanksgiving – it was deemed too controversial so was never given, but he planned to say: “We, the Wampanoag, welcomed you, the white man, with open arms, little knowing that it was the beginning of the end; that before 50 years were to pass, the Wampanoag would no longer be a free people.”

In the years that followed that breaking of bread, the population of Native Americans was decimated by violence and disease. According to Mayflower 400 UK, around 4,000-5,000 Wampanoag live in New England today, and only six tribes are visible from the original 69 in the Wampanoag Nation.

Instead of celebrating Thanksgiving, some Native Americans instead honour November 25 as a National Day of Mourning, remembering all who lost their lives after the colonial settlers came to America. The day was initially founded by Frank James in 1970.

Kisha James, United American Indians of New England (UAINE) youth coordinator, who is Aquinnah Wampanoag and Lakota and the granddaughter of Frank James, has said: “We Native people have no reason to celebrate the arrival of the Pilgrims. We want to educate people so they understand the stories we all learned in school about the first Thanksgiving are nothing but lies. Wampanoag and other Indigenous people have certainly not lived happily ever after since the arrival of the pilgrims. To us, Thanksgiving is a Day of Mourning, because we remember the millions of our ancestors who were murdered by uninvited European colonists, such as the pilgrims.”

Robert Jensen, emeritus professor at the University of Texas, doesn’t personally celebrate Thanksgiving. Through his work, he says he’s tried to make sense of race and racism, noting: “Somewhere along the line it occurred to me to ask white America to think about what I would call the ‘racialised Holocaust’ that was the destruction of indigenous peoples”, which includes challenging “the mythologies that circle around Thanksgiving”.

Jensen suggests people in the US are much more open to these types of conversations than they were 20 years ago, but that doesn’t mean his critiques of Thanksgiving are widely welcomed.

Thanksgiving isn’t the only problematic holiday on the calendar, nor is it unique to the US. In America, national holidays including the Fourth of July and Columbus Day have troubled histories, and Australia Day is often referred to as ‘Invasion Day’, as it marks white settlers landing on indigenous land.

“Why do people want to turn away from, bury, deny the historical realities, which are now almost self-evident?” asks Jensen. “I think these issues are so difficult for many Americans, especially white Americans, [because] the United States is the wealthiest and most powerful country in the history of the world… And how did we get to be the wealthiest nation in the history of the world?”

Jensen argues this power and wealth came from a series of “racialised Holocausts”, the first being “the nearly complete extermination of indigenous people, which created the land base for the contemporary United States”. Holocaust is a strong word, but Jensen says: “I’m not being hyperbolic – the formation of the United States, the march across the continent, exterminated – depending on the numbers you use, and these are estimates – somewhere between probably 95 and 98% of the indigenous population [other numbers suggest around 90%]. That is the most extensive genocide in recorded human history. Without that, the United States would not exist.”

Facing up to the history of colonialism “forces us to re-evaluate the wealth and comfort we live with today”, which can be hugely uncomfortable, says Jensen.

“People who live with a fair amount of material comfort are not eager to engage in a thought process that may result in them having to give up some of that material comfort. It’s a simple human instinct – I don’t think it’s unique to the US.”

While Jensen’s views on Thanksgiving could be considered quite radical, he understands why people aren’t willing to do away with the holiday altogether. Many of his friends share his critiques, but say they “redefine Thanksgiving to be a day for family”.

Jensen continues: “I understand why they do that. I understand the intention, but holidays are, by definition, public celebrations. You can say, ‘In my household we don’t define Thanksgiving in that way,’ but there’s really no way to escape the dominant cultures framing and defining the holiday.”

Jensen accepts, “it’s a good thing for people to spend quality time together, it’s a good thing to cook at home, it’s a good thing for multi-generation families [to get] together on a regular basis – but none of that requires Thanksgiving… It’s not as if family unity in the United States hinges solely on Thanksgiving.”

So where does Jensen see Thanksgiving going from here? “I don’t expect to see significant change in my lifetime, but I’ve been wrong before,” he says. “For instance, I was one of those people who didn’t expect to see the election of a black president in my lifetime.”

“I suspect more and more people will start to celebrate it in different ways,” he continues. “They will perhaps talk more during a Thanksgiving gathering about the importance of this [history], but I don’t see the holiday going away anytime soon.”