Maxwell, 58, has been named in multiple lawsuits by women who said they were abused by the disgraced US financier, who killed himself last August.
She was arrested Thursday morning in New Hampshire, said Nicholas Biase, a spokesman for the US attorney's office.
Maxwell, whose whereabouts have been unclear since the arrest last summer of Epstein, has been under investigation for allegedly facilitating Epstein's recruitment of young girls and women.
In the wake of Epstein's suicide in August 2019, public pressure has mounted to hold those who might have assisted him -- perhaps including Maxwell and a coterie of young women who allegedly worked under her -- accountable not only for his actions, but also for their own roles.
In that investigation, Maxwell has remained a significant target. She has denied wrongdoing, and in a deposition has called at least one of her accusers "a liar."
So who is Maxwell? Why was she hiding, and what accusations does she face?
Who is Ghislaine Maxwell?
Born in 1961, the British socialite grew up in the idyllic Oxfordshire countryside and is the daughter of Robert Maxwell -- a Czech-born newspaper tycoon and British lawmaker who died under mysterious circumstances. The media magnate fell off his luxury yacht -- called "Lady Ghislaine" -- around the Canary Islands in 1991. He was posthumously discovered to have committed a massive pension fraud against his employees.
According to Roy Greenslade, who worked for the media mogul as editor of The Daily Mirror in the early 1990s, Maxwell "doted" on Ghislaine "in a way that he didn't on his sons."
"He was a monstrous father," Greenslade recalls. "He treated his whole family very badly." But when it came to the youngest of his nine children, Maxwell "treated her more leniently than any of them."
In his biography of the tycoon, "Maxwell: The Rise and Fall of Robert Maxwell and his Empire," Greenslade recalls one evening in particular when he was sitting in an office with Maxwell and the daredevil teenager wandered in. He says Maxwell gave his daughter a scolding for "always taking risks, doing stupid, dangerous things" after she had a near-fatal accident after diving off a boat.