A kind of eerie calm has settled over this last French colony on the African continent on the eve of a referendum for its independence that has been preceded by a storm of international controversy.

For about a year, the future of this port state known as the French Territory of the Afars and Issas has been the subject of intense negotiations involving France, half a dozen feuding local political parties and the Organization of African Unity.

The result was a French decision in March, following a conference in Paris with two of the five local parties, to hold both a referendum and elections for a National Assembly this voters will approve the independence Sunday. France is so certain that the plan that it has already fixed June 27 as the independence date.

This leaves open the thorny issue of whether the two main feuding ethnic groups here, the Issas and the Afars, can agree to build a nation together or whether the future Republic of Djibouti is destined to become a warring community like Lebanon Cyprus.

Further complicating the birth or Africa's 49th nation - the smallest on the continent - is a longstanding struggle for control of the territory between the two neighboring countries. Somalia and Ethiopia.

"It will be six months to a year before we know for certain whether Djibouti can survive as an independent state," remarked one French observer here. After months of pessimism about the territory's fate, however, there now appears to be a growing sentiment that it can survive.

The main reason for this new-found cautious optimism is that the internal political squabbling between Afar and Issa leaders has abruptly ceased. This is apparently caused by a fear of being devoured by one of their neighbours. The international community led by the Organization of African Unity has made it clear that it wants an independment Djibouti so peace can prevail in the Horn of Africa.

The territory, distinguished by its intolerable heat, stony wasteland and absence of all natural resources, is inhabitated by somewhere between 215,000 and 275,000 nomads, depending on the season. Most are Afars and Issas, although there are also some Somalis and Arabs.

Traditionally, the Afars have been regarded as pro-Ethiopian because many of them live in Ethiopia part of the time and the Issas as pro-Somali since they are a Somali-speaking people who spread across borders both into Somalia and Ethiopia.

France traditionally has favored the Afars, following a pro-Ethiopian line and backing an Afar-dominated government in the territory, although the Issas are more numerous. In the past year, however, France has reversed its policy, abandoning Afar leader Ali Aref, and facilitating the establishment of a pro-Somali Issa-dominated government to run the country after independence.

On Sunday, 103,000 electors, a slight majority of them Issas, will vote for a single unopposed list of 65 deputies who will form a constituent assembly. The assembly will draft a constitution and form an interim government.

The Afar parties have fielded no opposing list, and Ali Aref, has given his blessings to what is certain to be an Issa-dominated independent government.

In return, the main Issa party, the African People's League for Independence, has given the Afars 30 seats of the 65 in the new assembly. Another two have been given to the small Arab community in an effort to unify all ethnic groups.

An unprecedented number of foreign observers have come here for the referendum. The United Nations, OAU, the Arab League and even Ugandan leader Idi Amin have sent delegations.

The main causes of concern are Djibouti's strategic location on the Straits of Bab el Mandeb - the narrow gateway to the Red Sea - and its potential as a powder kep that could easily set off a war between Ethiopia and Somalia, engulting the entire region and involving the big powers.

Somalia has long harbored a dream of seeing the territory integrated into a Greater Somaliland embracing all Somali speaking peoples in this region.

For Ethiopia, the territory is a vital link to the outside world. The port here and the 485-mile railroad from Djibouti to Addis Ababa presently handle about 60 per cent of Ethiopia's imports and exports.

Djibouti has become even more important to Ethiopia since the separatist movement in its northern Eritrea province has begun to threaten access to the Red Sea ports of Assab and Massawa.

Ethiopia has renounced its historic claims to the territory while Somalia has not, although it has agreed to recognize Djibouti's independence and territorial sovereignty. Still, the Ethiopians are convinced that sooner or later Djibouti will fall to Somalia, possibly through a federation obtained by referendum after independence.

France's abrupt shift from support for the Afars to the Issas has infuriated the Ethiopians and strengthened their fears of a Somali takeover.

It was the Somali-Ethiopian feud that allowed France to maintain its presence here long after it had given independence to its other African colonies in the 1960s. Long the peacekeeper in the Horn of Africa, France is now concerned that a hasty departure might provoke a war.

To maintain peace during the transition period and immediately after independence, France has assembled a naval force of 18 ships, led by the aircraft carrier Clemenceau. In addition, it has about 6,500 military personnel, including the Foreign Legion in the territory.

France, with strong backing from neighboring Arab states and the United States, seems determined to prevent outright Somali domination by doing everything possible to establish an independent Djibouti government with as much international recognition as possible.