The scope of the independent inquiry into child sex abuse in England and Wales will not change, the new home secretary has told MPs.
Amber Rudd told the Home Affairs Select Committee the inquiry must "look at the historic element of these abuses".
She also said that criticisms from the inquiry's former chairwoman, who wrote to the committee, were "not correct".
Justice Lowell Goddard's letter said the inquiry should focus on current child protection and future changes.
The inquiry was set up in 2014 and announced that 13 initial investigations would look into allegations against local authorities, religious organisations, the armed forces, public and private institutions and people in the public eye.
It has been beset by problems, and last month Dame Lowell became the third chair to quit the inquiry.
Giving evidence to the committee, Ms Rudd said there would be no review of the inquiry's terms of reference.
"Understanding what happened is so important to getting right what we think is going to help now and in the future," she said.
Asked why she thought Dame Lowell had stepped down from her role, Ms Rudd said she believed "ultimately she found it too lonely, she was a long way from home".
"I never met her, so I can only conclude from what she set out in the letter that she knew what she was doing, because I thought that the letter was pretty well informed about what the issues were and really show that she cared about the issues.
"But she did set out in the letter that she didn't feel she could actually deliver on it," she said.
MPs raised a number of questions about the truth of some of Dame Lowell's criticisms, which included saying the inquiry was under-resourced and that she had felt she did not have enough independence in her role.
Factually 'incorrect' letter
Ms Rudd said it was "incorrect" of Dame Lowell to suggest that the inquiry had suffered from "operational difficulties" and a lack of resources, because the inquiry had spent less than it was allocated last year and returned about £2.5m to the Home Office.
"The Home Office and the now-prime minister were always determined to ensure that there were sufficient resources available," she said.
Ms Rudd was also asked to respond to Dame Lowell's comments that she had been "handicapped by not being given a free hand to recruit staff".
The home secretary said the chairperson could "appoint who they want to the inquiry" and encouraged the committee to put the issue to Dame Lowell "if you feel it is of such importance".
Professor Alexis Jay, Dame Lowell's replacement, will be able to reassure the public and survivors, Ms Rudd said, because she is confident the chairwoman aims to "proceed with pace, clarity and confidence" and does not want the inquiry to "go on endlessly".
Ms Rudd added Prof Jay would be paid "substantially less" than the £500,000 a year paid to Dame Lowell, and she promised to disclose the new chairwoman's salary to the committee as soon as it was finalised.