Ms. Wruble, a central organizer of the march, says she agrees that white women, including Jews, should grapple with their racial privilege. She put out a call for women of color to join the planning team and was connected with Ms. Mallory and Ms. Perez. At that first meeting, Ms. Wruble said, they seemed to want to educate her about a dark side of Jewish history, and told her that Jewish people played a large role in the slave trade and the prison industry.

“I was taken aback,” said Ms. Wruble in her first extensive interview about her experience organizing the Women’s March. “I thought, ‘Maybe there are things I don’t know about my own people.’”

She said she went home that night and searched Google to read about the Jewish role in the slave trade. Up popped a review of “The Secret Relationship Between Blacks and the Jews,” a 1991 book by Mr. Farrakhan, which asserts that Jews were especially culpable. Henry Louis Gates Jr., a Harvard professor, has called the book the “bible of the new anti-Semitism.”

Ms. Wruble said she did not dwell on the issue because she wanted to work together on the march, which was only two months away. Ms. Mallory and Ms. Perez brought a friend on board, Linda Sarsour, a Palestinian-American activist. The three women — and another woman named Bob Bland, a white fashion designer who created one of the first Facebook pages about the march — became the event’s official leaders. They were widely featured in the press as the public face of the movement.

Behind the scenes, Ms. Wruble said she felt cast aside.

She said she was told by one of the march leaders that “we really couldn’t center Jewish women in this or we might turn off groups like Black Lives Matter.” While Black Lives Matter is a diffuse movement, some activists have issued statements expressing solidarity with Palestinians under Israeli occupation.

At one point, Ms. Wruble said she asked about security for the march and was told by the leaders that the Nation of Islam would be providing it.

“I said, ‘You are going to open up the march to intense criticism,’” Ms. Wruble said, warning that it would be a red flag for Jews. She said they dismissed her concerns in a heated email exchange and accused her of unfairly maligning the Nation of Islam.