The remote chain of idyllic South Sea islands that inspired James Michener's "Tales of the South Pacific" has become the setting of a bizarre tragicomic drama of British-French colonial rivalry.

Its pits against each other bitterly antagonistic Anglophone and Francophone factions of the black Melanesian natives of the New Hebrides Islands 1,500 miles northeast of Australia, which have been ruled by bickering British and French officials in a unique colonial arrangement for the last 74 years.

British-educated mostly Scottish Presbyterian blacks have won majority control of the parliamentary government that is to assume power when the group of about 80 islands are granted independence at the end of July.

But French-educated blacks have seized control of the largest island, Espiritu Santo, and set up a separate, independent state under the leadership of an Eurasian former bulldozer driver named Jimmy Stevens. His small army of 800 plantation workers, armed with spears, bows and arrows, is backed by 50 disgruntled white French plantation owners on the island and an eccentric American businessman in Carson City, Nev., named Michael Oliver.

The French plantation owners fear loss of their position under Anglophone Melanesian rule, according to British officials, and Oliver has encouraged the French-speaking rebels to set up a model "libertarian" state of complete freedom from all restrictions including taxes.

Oliver said in a telephone interview from Carson City today that he has given the Francophone rebels financial support and helped them write a "libertarian" constitution for their independent state. He said he had been impressed by his first meeting years ago with Stevens, who has been seeking independence of the New Hebrides from Britain and France for two decades.

Oliver said he also wanted to save the islands from what he said was "Marxist-Leninist" influence on the Anglophone leader and designated as prime minister, black Anglican priest Walter Lini. Lini and the British and French governments have denied knowledge of any such influence.

The Stevens-led rebellion on Espiritu Santo and the nearby smaller island of Tanna, where one of the native tribes worships the Duke of Edinburgh, Queen Elizabeth's husband, as its god, has been growing ever since the Francophones lost last autumn's election to Lini's Anglophones. Stevens has established for Santo its own flag, national anthem, currency and coins stamped with Stevens' likeness, plus the constitution drawn up by Oliver in meetings with the rebel leaders on Santo and in Carson City.

British and French officials did nothing about this until the Lini government police had to put down a small uprising on Tanna, where rebels dynamited a road and briefly kidnaped some police officers.

Then, this past week, after negotiations between Lini and Stevens failed to resolve their differences, Stevens' small army seized key positions on Santo and imprisoined its British district commissioner and about 40 police officers loyal to Lini's government, which is based in the New Hebrides capital of Vila on the island of Efate.

The British resident commissioner in Vila has sent a British ship to evacuate about a dozen British nationals from the renegade island. He also has warned the rebels not to harm them and to release their prisoners.

British diplomats here have set up an emergency meeting Monday between Deputy Foreign Minister Douglas Hurd and his French counterpart in Paris to decide what to do next about the rebellion.

Despite their joint rule of the New Hebrides since 1906 -- when they signed an agreement to end tension between French settlers and Scottish missionaries in the islands -- the historic antipathy between the British and French has marked their administration of what is known diplomatically as a comdominium colony and the arrangements for its independence.

The British and French have run rival legal systems, police forces, schools and other institutions on the islands. Visitors have had to declare on arrival whether they wished to be governed by British or French law, with the French system boasting wine for its prisoners jail.

The British and French have been unable to agree on just how all this should be merged into the hybrid island nation of more than 100,000 people to be created July 30. They also have done little to try to diffuse the tension between the English- and French-speaking factions or to improve the economy of the archipelago, which has meager resources beyond coffee, cattle and fish, according to British author Alexander Frater.

Most of the roads, airfields, and wharves and many of its hospitals and other facilities were built by American armed forces who used the islands during World War II as a base to attack the Japanese in New Guinea and the Solomon Islands to the north.

The Rodgers and Hammerstein musical "South Pacific" was based on Michener's wartime novel set in and arond the New Hebrides island of Aoba, and the French plantation whose owner sang "Some Enchanted Evening" still exists.

Frater wrote in the Sunday Observer magazine after a recent tour Melanesians "withdrawn, gentle, introspective people who spend their days fishing or attending to their gardens." But he said Britain and France will be "leaving behind a tiny, impoverished republic grotesquely ill-prepared for independence."

British officials privately accuse the French of dragging their feet on independence arrangements because of the English-speaking government that will take over and the unhappiness of the French who predominate among the islands' several thousands white residents.

Jimmy Stevens, who was the islands' first agitator for independence, made appeals to the United Nations and visited with French officials in Paris in 1975. But he was overtaken politically by British-educated Lini, whose English-speaking Vannuakku Party first won local elections in the islands in 1975. A Vannuakku-led uprising in Vila in 1977 led to a British and French agreement to grant independence this summer.

Stevens and Francophone leaders on other islands accuse the Anglophones of rigging last autumn's parliamentary elections, which Nevada businessman Oliver cites as evidence that the English-speaking leaders are part of plot to take over the islands undemocratically.

Oliver once belonged to the rightwing Phoenix Foundation, which tried unsuccessfully to establish tax-free independent states on Abaco in the Bahamas and Minerva Reef in Tonga. But he said today that he no longer has anything to do with the Phoenix Foundation and merely wants to save the New Hebrides, the Francophones and the white French settlers from outside domination "by either communists or fascists" and discrimination by the Anglophones.

Although he has had difficulty reaching anyone on Espirtu Santo since the current insurrection began, he said he sent work through friends on other islands that Stevens should release his prisoners unharmed.