The Republic of New Afrika had a revolutionary idea when it was formed in 1968: The U.S. government would set aside six Southern states for black Americans as a "payback" for slavery.

The RNA went so far as to establish "the first African capital in the northern Western Hemisphere" in Hinds County, Miss., but police and FBI raids on the headquarters left the group in disarray. By 1971, the RNA had been dissolved, or "destabilized" as some members claim.

Today, a reformed and relocated Republic of New Afrika marks the passage of 18 years since its founding with a "humanitarian" plea to President Reagan for the release of RNA members and other "political activists" who were arrested and jailed during those turbulent times.

But instead of issuing communiques from the embattled capital, consecrated El Malik, the group yesterday held a news conference in the new home town of the provisional RNA government: Washington.

It was a curious evolution for this once-feared group, which in some ways seems stuck in a time warp. Didn't the failure of such small-time creations as "Soul City" prove that the idea of a black nation within America had lost its appeal? And didn't the campaign of Jesse L. Jackson for president prove that most blacks had bought into the political life of these United States?

Imari Obadele, president of the RNA, remains adamant in his belief that blacks would demand a nation of their own if they knew that international law entitled them to one. "The 14th Amendment, an attempt to bestow citizenship on the Africans, newly freed from slavery, does not stipulate that the Africans had to become Americans," he said. "It meant they were free -- free to choose to return to Africa, stay here and become Americans or stay here and form a separate country. Integrationists like Jesse Jackson would be free to stay and become American." And what would this new nation be like? The RNA held elections in November 1984, and they offered some insights.

The elections were held on street corners in various cities, with fairly strong showings in Philadelphia, New York, Chicago and here in Washington.

"Because of our limited resources and the lack of access to the media, our efforts were restricted," said Thomas Stanley, a Washington native who was elected minister of information. "But it was still an open and honest election, and people took it seriously." Stanley says RNA membership today is between 5,000 and 10,000 people, although the group regards all black Americans as citizens. "We divide them into those who are conscious citizens or those who are unconscious," Stanley said.

Under the new government, judges were elected and empowered to perform marriages and divorces, and also to issue name-change certificates for those wishing to discard their "slave names" for African names.

A minister of interior was elected to issue passports, among other duties.

Also under the new rules, male citizens of the Republic of New Afrika would be allowed to have more than one wife -- "because of the shortage of men," says President Obadele, who is 55. Says Stanley, "I'd move back to Mississippi in a minute."

Until that day, the RNA will be operating out of Washington, its traditional rhetoric about the "military viability" and "second-strike capabilities" of their new country significantly toned down in favor of drawing and educating new members. "I like D.C.," said Obadele, who moved here from Philadelphia soon after his release from prison in 1983, where he had served five years on charges of conspiracy to assault federal officers who raided the Hinds County headquarters. "Washington has a long black nationalist population that is cohesive. I like the unity here."

With a PhD in political science from Temple University, Obadele no doubt is aware of the uphill battle he faces. But surely he did not miss the irony of establishing a provisional national capital in the District of Columbia, a city that has tried but failed to become a state.