Correction: A photo caption with a print version of this article misspelled the last name of Gary Vollmer.

The unexpected and potentially rotten news that the world will end on May 21 rolled into the District on Thursday morning, plastered on a caravan of five recreational vehicles that parked near the Washington Monument.

“Have you heard the awesome news?” the side of the RVs asked, in big bold letters. “The End of the World is Almost Here!”

As if the message weren’t scary enough, the dozen or so occupants of the RVs — vanguard of a national campaign funded by a fundamentalist Christian radio network and fueled by bus ads and Internet buzz — wore highlighter-bright yellow shirts that said “Earthquake So Mighty, So Great.” They offered pedestrians handouts saying there was “ marvelous proof” that “Holy God will bring judgment day on May 21, 2011.”

The Rapture, they warned, is upon us.

A woman waved off the pamphlet: “Already have one.” A jogger ran right past. “No thanks,” said another. A tourist simply said, “No.” Many people said exactly nothing.

Although the District is apparently a tough audience for doomsday forecasts — despite the power here to make something like it happen — many Americans have been captivatedby the idea of the end of time since the country’s beginning. Some have even been so bold as to pick a date. William Miller, who spawned a 19th-century religious movement that remains visible today, is the most classic example: He created a nationwide stir when he predicted that Jesus would return and the world would end before March 21, 1844. (He was stood up.)

“In American history, you have always had a fascination with this stuff,” said Doug Weaver, professor of religion at Baylor University.

End Times, as the phenomenon is known, has spawned an economy that rivals the GDP of small countries. There have been scores of books, movies, video games and albums that revolve around Armageddon and the end of the world.

There was, among others, the 1991 movie “The Rapture,” starring Mimi Rogers and David Duchovny. Tim LaHaye and Jerry B. Jenkins, authors of the “Left Behind” series, have sold more than 63 million books. Even Johnny Cash dabbled in End Times lyrics, particularly in his popular song “The Man Comes Around.”

“This is a cottage industry,” said Weaver. “People really love this stuff.”

And for many Christians, it is a core part of their beliefs. About 41 percent of Americans think that Jesus will return before 2050, according to a 2010 poll by the Pew Research Center for the People and the Press.

Prior prophecy

The man pushing the current forecast is Harold Camping, an 89-year-old Christian fundamentalist radio host and co-founder of the Family Radio network, which broadcasts on dozens of stations across the country. His group has sponsored the end-of-the-world caravan and plastered cities, including Washington, with billboards and signs.

This is not Camping’s first end-of-the-world prophecy. In a 1992 book, he predicted that the world would end in 1994. When he woke up in 1995, clearly something had gone wrong.

“It’s just like anyone who invents something or comes to a truth or any technician — they don’t immediately make a finished product,” he explained. “I did not come to the finished product until three years ago. It was at that time that God showed some exquisite proof.”

This time, he insists that he’s right, and by lunchtime Thursday, about 50 area residents joined up with the caravan to support his message. Among them was Gary Vollmer, who took a leave of absence from the Department of Homeland Security to spread the word. He’s supposed to go back on May 23. “But I’m not going back,” he said. “I’ll be gone on the 21st.”

That’s when a great big earthquake is scheduled to occur. “The remains of all the believers who have ever lived will be instantly transformed into glorified spiritual bodies to be forever with God,” Family Radio says on its Web site. “On the other hand the bodies of all unsaved people will be thrown out upon the ground to be shamed.”

Tony Moise, a 47-year-old insurance underwriter from Silver Spring, quit his job to prepare. “It will be hell on Earth,” he said, taking a break from handing out material. “You won’t want to be around on May 22. There will be no electricity, no power, no water.”

Camping, an engineer by training, says he came up with the very precise date of May 21 through a mathematical calculation that would probably crash Google’s computers. It involves, among other things, the dates of floods, the signals of numbers in the Bible, multiplication, addition and subtraction thereof. Camping describes his equations with absolute conviction.

“He seems to be the only one who understands the equation,” said Paul Boyer, a University of Wisconsin historian who studies apocalyptic beliefs. “But he has a very persuasive radio voice, and he preaches with absolute confidence, and there seems to be enough people that believe it all.”

But there are also many skeptics, including LaHaye, who has made a fortune selling books about the end, although he hasn’t picked a specific date. “I would assume he’s sincere, but many people can be sincerely wrong,” he said, noting that in the Old Testament, false prophets were stoned. “Camping is very fortunate we don’t do that anymore.”

A time certain

On Thursday, Brenda Forester, visiting from Michigan, got into a somewhat heated encounter with one of Camping’s followers, citing a passage from the Bible that says nobody knows when Christ will return.

“He will return,” Forester said, “but not on May 21st.”

Another man was so perturbed by the May 21 message that he brought over a woman he found on the street who needed money. He asked whether the Camping followers would give her some cash, because there was no need for them to keep money with the world ending. They did not.

Still, those in the yellow earthquake shirts insisted that the end was near, saying all signs point in that direction.

Boyer said End Timers who pick dates almost always make their prophecies in context with current events. In the 1800s, Miller relied on financial panics. To bolster his claim that “judgment days are coming,” Camping has mentioned the massive earthquakes in Chile, Haiti and Japan, as well as the recent tornadoes in the South. And to top that off, gay people are thriving.

“There has always been some homosexuality in the world, of course, but now it is successful everywhere it turns,” Camping said. “Whole nations no longer consider it a sin, even though it is a sin. It fits into place now — God has orchestrated this to indicate we are right at the end. We are at the threshold of being destroyed by fire and brimstone.”

The end will come sometime around 6 p.m. on May 21 — not 6 p.m. California time or New York time or Hong Kong time. The world will end at 6 p.m. only when it is 6 p.m. locally, Camping said, citing his calculations. “People will see this coming to them from around the world,” he said. “It will follow the sun around.”

Camping doesn’t seem exceptionally sad to at the notion of seeing the world go: “Frankly,” he says, “I wonder why this hasn’t happened sooner.”