"We, the people, declare today that the most evident of truths - that all of us are created equal - is the star that guides us still; just as it guided our forebears through Seneca Falls and Selma and Stonewall," Obama said.
The statement was the strongest that the president has made in support of the rights of gays during his presidency. In contrast, in his 2009 inaugural address, Obama did not mention gays and lesbians at all.
Obama's words also represented the first time a president discussed gay rights during an inauguration speech.
"It is now our generation's task to carry on what those pioneers began. For our journey is not complete until our wives, our mothers, and daughters can earn a living equal to their efforts," Obama said.
"Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law - for if we are truly created equal, then surely the love we commit to one another must be equal as well."
Gay rights activists throughout the region, such as the Rev. Don Crail, a retired Presbyterian minister living in Claremont, commended Obama for his framing the struggle for equality.
"He put it in the context of civil rights and it is, I think: It's the next chapter in equality in this country. I think instead of being
"I think gay marriage will become a reality in many more states in this next four years. He's also instructed his attorney general to not defend the Defense of Marriage Act. I think he's been prophetic on that issue."
Obama supported same-sex marriage in 2012 and pushed for the 2011 repeal of "don't ask, don't tell," which curtailed gays ability to serve openly in the military.
Crail was also pleased by the participation of gay poet Richard Blanco, who recited a poem during Obama's inauguration ceremonies.
"The fact that it's Martin Luther King's special day, I think it's very right and appropriate for him to let the world know how he feels," said Patti Loitz, president of the Pasadena chapter of Parents, Families and Friends of Lesbians and Gays.
Loitz said she doesn't think Obama's comments will necessarily translate into legal changes.
"We know how he feels, but he doesn't make the laws," she said. "It's just a matter of whether can they get the cooperation from all the parties involved."
Loitz wasn't surprised he would address gay rights during his speech: PFLAG had a float in Monday's inauguration parade - the first time the lesbian, gay, bisexual, and transgender community was represented in the parade.
"It fits right in with the message of equality for women, blacks and gays," she said. "It's at the forefront now."
Obama's evolving views on gay marriage accompany a shift in the views of many Americans: In the most recent survey on gay marriage by the Pew Research Center, 47 percent of the 3,008 adults surveyed in April supported gay marriage, 43 percent opposed it and 11 percent of those surveyed didn't know.
Four years ago, only 39 percent of those surveyed supported it and 51 percent opposed it.
And in 2004, shortly before George W. Bush won his second term in office, only 31 percent of those surveyed supported it and 60 percent opposed it.
Members of the Long Beach and Signal Hill's gay community also reacted positively to Obama's speech and found his words - spoken in front of the public as well as some U.S. Supreme Court justices - meaningful at a time when landmark judicial issues such the Defense of Marriage Act and Proposition 8 are being examined.
The Defense of Marriage Act forbids federal officials from recognizing same-sex marriage and Prop. 8 is California's ban on same-sex marriage.
"The idea that he said that love should be shared by all - he was spectacular," Signal Hill Councilman Larry Forester said.
Forester said the president has come a long way from his initial views on gay marriage, which Obama did not favor until recently despite supporting gay rights.
"Over time, he finally decided that love is love and love between two people of the same sex is love between two people of the opposite sex," Forester said.
"He said it to the public and I could not be more elated."
Long Beach Vice Mayor Robert Garcia also applauded Obama's speech and its emphasis on civil rights for not only the LGBT community but for women and minorities.
"He talked about America being at its best when it's equal and that's what came across for a lot of people," he said.
Obama's words may help further marriage equality, Garcia said, adding four more states passed same sex marriage laws after the president spoke out in favor of gay marriage about a year ago.
"It's a step forward when our leaders acknowledge that we have to work for all Americans, that all Americans should be treated equally," Garcia said. "It's going to make the country stronger."
Staff writer Karen Robes Meeks contributed to this report.
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