By 2012, Mr. Long had moved — briefly, apparently — to Tuscaloosa, Ala., where he spent one semester at the University of Alabama. He majored in business. He made the dean’s list. The University of Alabama police had no interactions with him during his time there. Mike Mansur, a spokesman for the Jackson County prosecutor’s office, which covers most of Kansas City, said his office also had no record of contact with Mr. Long.

He also attended Clark Atlanta University during the 2012-13 school year, and was in good academic standing, a university spokeswoman said. Although he claimed to be on the dean’s list there, he said he had dropped out, sold his two cars, gave away his possessions and traveled to Africa.

Mr. Long appeared to be obsessed with the idea of self-improvement, for himself and for others, and he embraced more esoteric means of achieving those goals.

While traveling to Burkina Faso, Egypt, Ethiopia, Ghana, Kenya, Rwanda, Tanzania and Uganda, he said, he wrote three books, covering topics like “holistic detoxification for health, well-being and success”; the “ancient esoteric secrets of the Pineal Gland”; and the “124 Universal Laws and their use in the Laws of the Cosmos.”

In 2015, Mr. Long filed the petition to change his name. In his statement of intent, he said he was a member of an “indigenous society” called the United Washitaw De Dugdahmoundyah Mu’ur nation. It was apparently a reference to the Empire Washitaw De Dugdahmoundyah. On its website, the group says it is “a multicultural, highly spiritual nation of aboriginal, indigenous Americans.”

The group is largely African-American and subscribes to a “sovereign citizen” ideology holding that members are “no longer beholden to any form of government,” said Ryan Lenz, a senior writer for the Southern Poverty Law Center, which tracks extremist groups.

On Monday morning, a man who answered a phone number on the website and said he was a leader of the group, Fredrix Joe Washington, said he had never heard of Mr. Long.