Warren said she wrote that based on stories her family told about their heritage.
The 69-year-old from the U.S. state of MA has already become a main target of Trump, who has dubbed Warren "Pocahontas" for previously identifying herself as a Native American, a controversy that has plagued the run-up to her candidacy.
Trump refers to Warren as "Pocahontas", a slur referencing accusations that she falsely claimed Native American ancestry in a Harvard directory.
Trump campaign manager Brad Parscale said in a statement Saturday that Warren has been "exposed as a fraud by the Native Americans she impersonated and disrespected to advance her professional career, and the people of MA she deceived to get elected". We can't afford just to tinker around the edges, a tax credit here, a regulation there.
I think Warren would make a great president - she is a real fighter for the working people of our nation.
"This is the fight of our lives". Because the man in the White House is not the cause of what is broken. Kamala Harris and Cory Booker already in the race, and others, like Sens.
Warren spoke at the site of the "Bread and Roses" strike of 1912, which pitted thousands of textile workers, majority women and many of them immigrants, against mill owners in a dispute over pay and working conditions that ended with the state becoming the first in the U.S.to pass a minimum wage law.
How much effect the negative headlines will have on her in a crowded field will likely depend on how, or whether, Warren can put the controversy behind her. Warren's choice of site is a clear nod to her campaign message of a system rigged by powerful elites and corporations against the middle and working classes. Warren has spent the past decade in the national spotlight, first emerging as a consumer activist during the financial crisis.
Rep. Joseph Kennedy (D-Mass.) - the grandson of former Attorney General Robert Kennedy and grand-nephew to former president John F. Kennedy and Sen.
Warren was introduced by a few members of Congress who also endorsed her, including Massachusetts Sen.
The report, which marked the first instance yet of Warren making the assertion in her own handwriting, prompted new apologies from the senator. Viewed alongside a new proposal from Sanders to hike the estate tax, Warren has positioned herself at the center of the progressive push to reduce corporate influence in Washington and economic inequality across the country. She recently unveiled a proposal that pushes the frontier to a new place: directly taxing the very rich. Later in the week, Warren plans to visit South Carolina, Georgia, Nevada and California.
Unable to overcome Republican opposition to become the Director of the CFPB, Warren instead challenged and defeated Republican incumbent Senator Scott Brown of MA in 2012.
Warren has often spoken of how her parents eloped after her father's family disapproved of his future wife's Native American lineage, but Warren for years could never produce documentation to bolster her claims.
Ms Warren has apologised for taking the test.