Rep. Charles A. "Dutch" Ruppersberger was considering running for governor of Maryland 12 years ago when an operative for a political foe approached him with a word of caution.

"Dutch, you belong to an all-white, all-male secret society. I'm giving you a heads-up that we plan to make an issue of it," he recalls the operative saying.

"Tell anybody you want," the congressman remembers replying. "The world should know more about what it means to be a Mason."

Ruppersberger, 68, told the tale Sunday as part of the opening ceremonies for the Conference of Grand Masters of Masons in North America, an annual convention of the 500 or so individuals who serve as leaders for the 2 million Freemasons who live in the United States, Canada and Mexico.

The Freemasons, the oldest men's charitable organization in the world, hold the convention in a different city each year.

This year's affair, the 101st in history and the first to be held in Baltimore, began Sunday at the Marriott Waterfront Hotel and continues through Tuesday.

The 60 or so grand masters who head the grand lodges, or main headquarters, within each state and Canadian province, among other jurisdictions, were to compare notes on the progress of their charitable and fundraising activities, from campaigns to help locate missing children to supporting medical centers.

Each brought with him a handful of officers and supporters.

Conference chairman John Cooper, the grand master of California, kicked off the orations by announcing the convention's theme: "reclaiming our heritage for a better tomorrow." It seemed an apt idea for a brotherhood many say dates to the 1300s in England.

Most Masonic scholars agree the organization arose from the stonemasons' guilds during the Middle Ages, labor organizations that declared their members' moral and economic independence from the British monarchy.

Individuals who belonged valued thrift, liberty, strong moral character and a belief in a Supreme Being, traits Masons say are still essential to their mission of volunteering to help the oppressed and the less privileged, particularly children.

By 1717, records show, four lodges in London formed the first Grand Lodge of England, and within three decades, the fraternity had spread throughout Europe and the American Colonies, where many of the men who helped shape the early United States were members, including George Washington, Benjamin Franklin and Paul Revere.

Pioneer Davy Crockett, financier Andrew Carnegie, musical icon Duke Ellington, Presidents McKinley, Truman and Johnson and Gen. Douglas MacArthur are among the influential Americans who have joined the brotherhood.

Then as now, potential members had to first contact their local lodge, then meet that lodge's declared standards of good character.

Once approved, they join during ceremonies that include rituals they are sworn not to divulge.

Members say the secrets are simple matters that help preserve a sense of continuity through time, but some acknowledge the secrecy has helped convince many outsiders that Masons are a cult, that they wield untold political power behind the scenes, even that they're plotting to take over the planet and create a "New World Order."

The idea makes members like Robert D'Antonio laugh.

"I'm not a reptile. I don't eat children. I don't know how we could take over the world when we can't even agree on where to have a fish fry," said D'Antonio, a Ph.D. in tropical diseases who serves as special assistant to Gerald Piepiora, grand master of Maryland.

The only "secret," members say, is their quiet resolve to improve the lives of young people through missions such as the Student Assistance Program, a nonprofit organization supported by Masons that teaches educators how to spot children who may be struggling with hidden problems and get them help before it's too late.

That and their sense of fraternity. "Our real secret is the sense of brotherhood we have as we try to make good men better," said Mark Genung, grand master of Indiana.

Ruppersberger never did run for governor, but he has been a Mason for 42 years.

"We should be more open about who we are," he said. "Masons help build what's best in the human character."

jonathan.pitts@baltsun.com