A fuller, more complicated picture emerged Sunday of the videotaped encounter between an American Indian man and a throng of high school boys wearing "Make America Great Again" gear outside the Lincoln Memorial.

Interviews and additional video footage suggest that an explosive convergence of race, religion and ideological beliefs, against a national backdrop of political tension, set the stage for the viral moment. Early video obscured the larger context, inflaming outrage.

Leading up to the encounter Friday, a rally for indigenous people was wrapping up. Dozens of students from Covington Catholic High School in Kentucky, who had been in Washington for the March for Life rally, were standing on the steps of the Lincoln Memorial, many of them white and wearing apparel bearing President Donald Trump's slogan. There were also black men who identified themselves as Hebrew Israelites, preaching their beliefs and shouting racially combative comments at the Indians and the students, according to witnesses and social media video.

Soon, the Indian man, Nathan Phillips, 64, was encircled by an animated group of high school boys. He beat a ceremonial drum as a boy wearing a red "Make America Great Again" hat stood inches away. It was a provocative image that rocketed across social media, leading many — including the students' own school — to condemn the boys' behavior as disrespectful.

But on Sunday, Phillips clarified that it was he who had approached the crowd and that he had intervened because racial tensions — primarily between the white students and the black men — were "coming to a boiling point." He added, "I stepped in between to pray."

There were diverging views about what really had happened. Conservatives and other supporters maintained that the students had been unfairly vilified out of context, while those affiliated with the Indigenous Peoples March said they perceived the combination of the group's size, behavior and political apparel as threatening.

But there was little resolution Sunday. By then, thousands of people had signed an online petition started by a graduate of the school to remove its principal, while in some circles Phillips was cast as a professional activist engaged in a publicity stunt.

Jointly, Covington Catholic High School and the Diocese of Covington apologized to Phillips and said they were investigating. "We will take appropriate action, up to and including expulsion."

In a statement Saturday, the president of the March for Life, Jeanne Mancini, distanced herself from the students, saying that "the pro-life movement at its core is a movement of love."

"Such behavior is not welcome at the March for Life and never will be," she said.