Bohemian John Sloan, artist Marcel Duchamp, and others ascended to the top of the Washington Square Arch almost 90 years ago and announced “the independent republic of Greenwich Village.”

Tonight, representatives of “real and possible countries” gather at the New School to compare notes on what exactly constitutes a country. The assembled “heads of state” will also attempt to recruit attendees to join them as citizens.

Speakers, including the consul general of Switzerland, Ambassador Raymond Loretan, will consider the basic prerequisites for creating a nation and the conditions necessary for a country to gain international recognition.

“How do you get somebody to believe in you?” one of the conference’s speakers, an international relations professor at the New School, Jonathan Bach, said.

While the international community has protocols that institutionalize recognition, “this recognition is always a little more fragile than it seems,” Mr. Bach said.

“Call them micronations, model countries, ephemeral states, or new country projects,” George Pendle writes in the Summer 2005 issue of Cabinet magazine, which has the theme “Fictional States.” The magazine co-organized the conference with the Vera List Center for Art and Politics.

“The world is surprisingly full of entities that display all the trappings of established independent states, yet garner none of the respect,” Mr. Pendle wrote.

Cabinet magazine’s editor in chief, Sina Na jafi, who is moderating the conference, said some micronations are more like “thought experiments.” There may be thousands of people who simply declare that their website is their country or state. Some of the most interesting cases are when “fiction has intersected with real structures,” Mr. Najafi said.

Kymaerica, for example, is a reinterpretation of America that divides the country into districts and “gwomes,” or footprints. Kymaerica puts up plaques around the country, including one in the stairwell of a club at 85 Ave. A.

Mr. Najafi said Kymaerica is a kind of “alternative reality” akin to the imaginative literary writing of Jorge Luis Borges. It will be represented at the conference by its geographer-at-large, Eames Demetrios.

The most whimsical country at the conference is the Kingdom of Elgaland-Vargaland. According to its founders, who are artists, the kingdom claims “all border territories between all countries on earth and all areas (up to a width of 10 nautical miles) outside all countries’ territorial waters.” It also annexes other interstitial areas such as the hypnagogic state between waking and sleep. The kingdom’s minister of audiology and its minister of lamination are expected to attend the conference. The country’s national anthem is played on a theremin.

A common theme of micronations is their “dire and hazardous geography.” “All the world’s good spots have been taken,” Mr. Pendle wrote. One panelist, artist Gregory Green, sent a letter to the United Nations claiming an uninhabited island 500 miles south of Tahiti that he called “The New Free State of Caroline.” Mr. Green lost to Tonga but is now filing a claim on an island off Antarctica.

The proceedings include a screening of a documentary film about Sealand, a principality that sits atop a World War II anti-aircraft tower located seven miles off coastal Britain. A pirate radio operator named Paddy Roy Bates landed there, dubbed himself “Prince Roy,” and declared independence in 1967. Like many other leaders of micro-entities, Mr. Bates has sold Sealand passports and stamps. Famously, Sealand even survived a coup attempt by a German professor.

Mr. Najafi said the history of micronations is rife with unethical behavior, such as charlatans selling dukedoms. He said there were also those engaged in irony and satire, as well as those who exagerate the formalities of statehood.

The conference concludes with a reception featuring wine from a real country, Hungary. Perhaps the next conference will invite microbreweries to celebrate the micronation.

The real and imagined leaders won’t be returning home immediately. Tomorrow, many will attend the opening of a new exhibit about micronations, “We Could Have Invited Everyone,” at the Andrew Kreps Gallery.

Tonight, conference: 5:30-7:30 p.m. (Theresa Lang Center, 55 W. 13 St.); reception: 7:30-9 p.m. (Vera List Courtyard, 66 W. 12th St.), the New School, 212-229-2436, free. Exhibit: Tomorrow through July 29, Andrew Kreps Gallery, 516 W. 20 St., 212-741-8849, free.