Where did we begin: a celebration of the 40th anniversary of one early demonstration rankles some longtime activists.

When was the official birth of the modern gay rights movement? Some say it came with the forming of the first gay fights group. Others argue it started with the Stonewall riots in New York City in 1969. But for Malcolm Lazin, executive director of the Philadelphia-based activist foundation Equality Forum, it was July 4, 1965. That's when a group of about 40 gay and lesbian demonstrators held a rally on the steps of Independence Hall in Philadelphia, so Lazin has declared 2005 the "40th anniversary" of the gay rights movement. It's a designation that has some longtime activists up in arms.

As part of its annual weeklong symposium and cultural festival, this year Equality Forum will host a giant rally on May 1 on Independence Mall. "It will be one of the most awesome experiences this town has ever seen," Lazin said. "And most important, it will all be free and open to the public so our history can be seen by all."

The event will feature a program rifled "40 Years, 40 Heroes," honoring the most influential personalities and figures in the movement, as nominated by an international panel of activists and historians, including Advocate editor in chief Bruce C. Steele. But not all of the demonstrators from that original Philadelphia rally, dubbed "gay pioneers" in a PBS documentary on the subject, see the 1965 event as the official beginning of the gay rights movement. Journalist and activist Barbara Gittings says she might take part in this year's commemoration, but she doesn't agree with Lazin's claim. In response, she sent to many friends a detailed list of historic gay rights events, including five that happened before the 1965 Independence Hall demonstration. "It's a real disagreement," she said.

Historian Eric Marcus, author of Making Gay History: The Half-Century Fight for Lesbian and Gay Equal Rights, argued that Equality Forum should be celebrating the movement's 55th anniversary. It was 1950 when eight men gathered in a Los Angeles apartment and founded the nation's first gay rights group, what would later be known as the Mattachine Society. "The organization that planned the 1965 demonstration at Independence Hall was a direct descendant of that original Mattachine group," Marcus said. "Perhaps Equality Forum can lead [its] celebration by setting the record straight and including the Mattachine Society's founders."

Regardless of the controversy, Lazin said, this year's event will stand as a historic marker of its own. "This is a huge opportunity for us to celebrate our history and know our role models."