For years, gay rights organizations and major civil rights organizations viewed each other warily. African-American leaders often saw the gay rights groups as insensitive to racial concerns, and some resented the movement’s use of civil rights language to make the case for same-sex marriage. Advocates for gay rights, in turn, sometimes blamed socially conservative African-Americans for their defeat in crucial electoral battles.

But since the relationship reached something of a crisis with the passage of Proposition 8, California’s ballot initiative against same-sex marriage, in 2008, leaders in both movements have made an effort to bring their groups closer together.

Now, a series of conversations among leaders in the gay, black and Latino communities have borne significant fruit: On May 19, the board of the NAACP formally voted to endorse same-sex marriage.

And then, last Tuesday, representatives of several national gay rights organizations gathered at New York City’s Stonewall Inn, often described as the birthplace of their movement, to announce that they would march to protest the New York Police Department’s stop-and-frisk practice, under which the police each year have been stopping hundreds of thousands of New Yorkers, most of them black or Latino, in an effort to prevent crime.

Some of the gay rights leaders specifically cited support from the NAACP for same-sex marriage as a reason they decided to oppose the stop-and-frisk policy.

“We need to find ways to strengthen our alliances and really strengthen our commitment to one another,” said Jeffrey Campagna, a national gay rights organizer who is coordinating the involvement of gay rights groups in the June 17 march against the stop-and-frisk practice.

Julian Bond, a former chairman of the NAACP and a founder of the Student Nonviolent Coordinating Committee, said he saw the association’s support for same-sex marriage as a way to acknowledge the contributions of gay rights advocates, most closeted at the time, in the civil rights movement.

“I knew these people, whom I just assumed to be gay, and I knew what they were doing on my behalf — and I hoped on their behalf, too,” he said. “I was grateful for it, and when the chance came, I wanted to pay them back.”

The same-sex marriage and stop-and-frisk issues are only the most visible signs of closer collaboration.

Around the country, gay rights groups have joined minority advocacy organizations in political battles on behalf of voting rights and affirmative action. And in California, Oregon and Colorado, gay rights organizations have formed partnerships with immigrants rights groups to fight aggressive immigration laws.

And even before the national board of the NAACP voted to support same-sex marriage, that organization and other civil rights groups got involved in marriage battles on the state level. In North Carolina, the NAACP paid for radio and print advertisements, direct mail and “robocalls” urging black voters to oppose an amendment banning same-sex marriage; the amendment passed in May. In Maryland, where the state Legislature voted to legalize same-sex marriage in February, the Rev. Al Sharpton of the National Action Network and Wade Henderson of the Leadership Conference on Civil and Human Rights were prominent supporters.

“You must be for the civil rights of everyone or you’re not for the civil rights of anyone,” Sharpton said last week.

One indication of the new rapport: Chad Griffin, who is taking over on Monday as president of the Human Rights Campaign, the nation’s leading gay rights group, plans to have lunch on one of his first days in Washington with the president of the NAACP, Benjamin Todd Jealous.

Jealous explained the newfound collaboration with a reference to Bayard Rustin, the pacifist and civil rights advocate who was black and gay.

“In the last four years, with the increase in hate crimes across the country, with states attempting to encode discrimination into their state laws and constitutions,” Jealous said, “it’s become clear that, just as Bayard Rustin admonished us all, that we would either stand together or die apart.”

The distance that has long existed between the gay rights and civil rights movements has complex roots. In addition to the strain of social conservatism that pervades many black Protestant churches, gay rights advocates’ use of the phrase “civil rights” and comparisons of the two movements have sometimes offended African-Americans, according to Michael Eric Dyson, a professor of sociology at Georgetown University.

“When gay and lesbian people say, ‘Hey, we understand, because we’ve been oppressed, too,’ and ‘Like black people, we …’ that’s a nonstarter for many black people,” he said.

Keith Boykin, an author who has written about homosexuality in the black community, said that “when people hear civil rights and gay rights, they think that people are trying to equate the two movements.” As a result, he said, “we sometimes get caught up in these hierarchies of oppression.”

For its part, the gay rights movement has sometimes struggled to be racially inclusive.

“Fifteen years ago, the leadership of the gay community, certainly in terms of organizations, was overwhelmingly white gay men,” said Marjorie J. Hill, the chief executive of GMHC, an HIV/AIDS organization.

Hill, who is black, said the more diverse gay rights organizations became, the more natural it was for gay rights and civil rights groups to form alliances.

The communication between the two communities has picked up since the disclosure in March of a memorandum by the National Organization for Marriage, the leading group opposing same-sex marriage in the country, that described a goal to “drive a wedge between gays and blacks” over same-sex marriage.

Leaders in both movements had already perceived a need to create relationships after gay rights advocates and minorities found themselves pitted against each other in fights over same-sex marriage.

“In the aftermath of Proposition 8, it was all about ‘the blacks and the Latinos, they didn’t vote for us,”’ said Andrea Guerrero, the executive director of Equality Alliance San Diego, a group that works with immigrants and minority communities.

“Similarly, in the immigrant community, there’s been a sense of ‘they only call on us when they need us for their issue — they never come and help us on our issues,”’ she said.

To address that divide, she and Delores A. Jacobs, the chief executive officer of the San Diego LGBT Community Center, decided to test political messaging that they hope could be used in future campaigns to advocate both immigrants’ rights and same-sex marriage.

After Oregon voters in 2004 approved an amendment banning same-sex marriage, with the major group supporting the amendment using an African-American talk show host as its spokeswoman, a gay rights organization called Basic Rights Oregon decided to review its own lack of diversity and its failure to form close relationships with minority communities, according to its executive director, Jeana Frazzini.

It decided to make pursuing racial justice one of its central missions and deepened a relationship with a Latino immigrants rights group, Causa. Since then, Basic Rights Oregon has fought local anti-immigrant ballot measures and pushed at the state level for illegal immigrants to be able to get driver’s licenses and, for those who came to this country as children, to be able to pay in-state tuition at public universities. Causa and Basic Rights Oregon have also joined forces to run an ad on Spanish-language radio to promote legalizing same-sex marriage.

In the ad, a woman describes how she and her husband struggled to accept their gay son, then says that she does not want him to face discrimination when he finds someone to marry.

“As a Latina, I believe in loving my neighbor, in treating others as we would like to be treated, and in never turning our backs on family,” the woman says. “Marriage has brought so much happiness to my life, and I wouldn’t want any member of anyone’s family — gay or straight — to be denied that chance at happiness.”

© 2012 The New York Times Company