The grand narrative of the United States does not include the Indigenous story.

For any serious student of history, this should come as no surprise. Forty-five weeks ago, I embarked on a series of historical news stories exploring the evolution of federal Indian policy, one presidential term at a time. Starting with George Washington and ending last week with Barack Obama, I probed each president’s personal history, his attitudes toward and relationships with Indians, and federal Indian policies enacted during his tenure in office.

I began with primary source material. I searched inaugural addresses, executive orders and messages to Congress. I read presidential papers and dull, self-aggrandizing autobiographies.

I also read the most recent biographies published about each president, starting by skimming the index for the terms “Indian” or “Native American”—and often coming up empty. Finally, I reached out to experts: professional historians, biographers, professors, museum archivists, and sometimes progeny of presidents themselves.

Going into the project, I mistakenly thought this information would be easy to obtain. How hard could it be to find a complete list of treaties? Or track speeches about Indian affairs? Or identify an expert on a specific president’s relationships with Indians? The answer: very hard. In some cases, it was next to impossible.

What I wanted, and what I asked for 44 times during phone interviews with experts across the country, was succinct summaries of each president’s contributions to Indian policy. What I got was a whole bunch of head-scratching. A whole slew of renowned experts who didn’t know what I was talking about.

Yes, there are exceptions, but the vast majority of presidential “experts” I queried knew almost nothing about Indians. I interviewed an Andrew Johnson biographer who had never read about the Navajo Treaty of 1868; my Gerald Ford source knew nothing about the Indian Self-Determination Act; and my Lyndon B. Johnson expert had never heard of the Indian Civil Rights Act.

Now, having spent more than 1,000 hours on this series, reading hundreds of documents and writing more than 50,000 words, I emerge with a list of sober truths.

First, when it comes to studies of American presidents, Indians are largely invisible. If you don’t believe me, go to the library and search for “Indian” in presidential biographies. Even when it’s in there, the corresponding entries are minimal; references are vague; and the portrayal of Indians is superficial at best, malicious at worst.

We hear all the time that history is whitewashed. That concept took on new meaning for me after I read 44 biographies and felt the cumulative effect of omissions, misrepresentations and clear Manifest Destiny agendas.

I could shrug off the slights once or twice, but ultimately, language matters. What we write and how we write it makes a difference.

Second, this whitewashing of history doesn’t necessarily come from biographers or historians, but from primary sources themselves. For example, Calvin Coolidge signed the Indian Citizenship Act in 1924, granting all Indians the privileges of U.S. citizenship, including the right to vote. The act was one of the most important pieces of legislation for Indians, but Coolidge neglected to mention it in his autobiography.

Jimmy Carter is guilty of the same omission. Although he signed the Indian Child Welfare Act in 1978, curbing the practice of placing Indian children with non-Native families and establishing regulations for keeping Indian children in their communities, Carter didn’t mention the word “Indian” in his 1982 autobiography.

In both of these instances, my takeaway is that the President didn’t know or didn’t care what he was signing. If makers of history don’t value their own contributions, can we really expect more from readers of history?

Third, American history tends to focus on “big-picture” presidents, but some of the more obscure or forgotten presidents actually did the most for Indians. For example, John Quincy Adams was an early advocate for Indians, calling existing policy “fraudulent and brutal.”

Rutherford B. Hayes supported Indian education; Warren Harding pushed for Indian citizenship; and Richard Nixon, most often criticized for his role in the Watergate Scandal, officially ended the termination era.

Ask an average American to name as many U.S. Presidents as they can. Most likely, they’ll get the big names like George Washington, Abraham Lincoln and Theodore Roosevelt. But when it comes to Indian policy, the more influential presidents often are the lesser known.

I spent a lot of time researching the Presidents this year. In the process, I learned for myself that Indians were systematically removed from America’s story.

I did not see Indians until I wanted to. Even then, I had to search long and hard for a version of history that told their story. And ultimately, I had to write that narrative myself.

To read about all the Presidents of the United States, visit ICTMN.