WASHINGTON – Sonia Sotomayor made history Saturday as she took the oath of office to become the first Hispanic US Supreme Court justice, and just the third woman on the court in its 220-year history.

Chief Justice John Roberts administered the oath in a brief televised ceremony held in a Supreme Court conference room, with some 60 of Sotomayor's friends and relatives present. Minutes earlier Roberts administered a slightly different oath in a private ceremony.

The event caps the spectacular rise of Sotomayor, 55, from a gritty working-class background through elite US universities and the federal bench to the top US judicial body, the final arbiter on legal matters in the nation.

The New York-born Sotomayor, whose parents came from the US commonwealth of Puerto Rico, took the oath with her left hand on a Bible held by her widowed mother Celina, as her younger brother Juan, a medical doctor, stood smiling by her side.

The country's 111th high court justice solemnly swore to "administer justice without respect for persons, and to equal rights to the poor and to the rich," and to "faithfully and impartially discharge and perform" all of her duties as a Supreme Court justice, "so help me God."

"Congratulations and welcome to the Court," Roberts smiled, as he shook her hand immediately after the oath.

Sotomayor was confirmed by a 68-31 margin in the US Senate on Thursday.

Her detractors accused her of being a "judicial activist" and focused for weeks on a 2001 remark to law students at a conference on Hispanic judges.

"I would hope that a wise Latina woman with the richness of her experiences would more often than not reach a better conclusion than a white male who hasn't lived that life," Sotomayor said at the event.

The remark made many conservatives nervous, with some calling her a racist. In the final poll, only nine out of the 40 Republican senators voted to confirm her.

Sotomayor, who has been a federal judge for 17 years, replaces outgoing justice David Souter, who announced his retirement in May after 19 years on the Supreme Court.

President Barack Obama, who nominated Sotomayor for the job, was not at the event but will hold a White House reception in her honor on Wednesday.

The public swearing-in ceremony was broadcast live on television -- a first, as the camera-shy justices do not allow televised broadcasts of its court sessions.

In what is seen as a symbolic sign of independence, Sotomayor chose to have the ceremony at the Supreme Court.

The last two justices to take the bench -- Samuel Alito and John Roberts -- were nominated by then-president George W. Bush and sworn in at a White House ceremony.

Sotomayor grew up in the Bronx, a working class borough of New York city. Her mother was a nurse and her father was a blue-collar worker.

She graduated from elite Ivy League universities, and was a Manhattan prosecutor and corporate lawyer before becoming a federal judge.

Sotomayor is the first Supreme Court justice nominated by a Democratic president since 1994.

The new justice will have little time to celebrate -- the first case she will hear, concerning the constitutionality of part of the McCain-Feingold campaign finance reform act, is scheduled for September 8.

Obama issued a statement on Sotomayor following the Senate vote confirming her to the bench on Thursday.

"I'm filled with pride in this achievement and great confidence that Judge Sotomayor will make an outstanding Supreme Court justice," Obama said moments after the Senate vote. "It's a wonderful day for America."

Hispanics are the fastest-growing US minority group. Most are Mexican-American.