Last year Samtcho Doudering Azina fled the Moursal section of this city back to southern Chad with approximately 100,000 of his fellow southerners, just ahead of rampaging Moslem guerrillas.

Kaadi Mahamat, having previously endured days of terror under the defeated southern soldiers, could sit out this particular bloodletting in Ndjamena with his brother Moslems.

Both southerner Samtcho, 32, and Moslem Kaadi, 30, were teen-agers when the Moslem rebellion against the southern-dominated government began in the mid-1960s. The two men's attitudes, life styles and dress reflect the deep divisions in today's Chad and the difficult to bridge gulf between the two cultures.

Today, the hundreds of small, square mud-walled houses of Ndjamena's Moursal neighborhood where most of the southerners lived stand empty. The once lively quarter is a silent symbol of the carnage that swept through this capital last February and March in massacres between Moslem and black southerners.

The Moslem section of the city, dominated by the high, slender misnaret towers of the Grand Mosque, is a beehive of activity with men in flowing gowns, turbans and brightly colored caps. The busy scene is testimony to the hard-won victory of the northern Moslems over the corrupt and discriminatory government of the southerners that was toppled after 14 years of warfare.

But there is still a tense, armed city divided into guerrilla strongholds by warring factions who rule in a fragile coalition here.

In addition, to about 3,000 guerrillas, another 8,000 civilians are believed to be armed.

Four hundred soldiers, the first contingent of an African peacekeeping force, arrived here recently from the Congo on Algerian Soviet-built Antonov planes. Groups from Benin and Guinea are expected soon. The African troops are scheduled to replace a French force of 1,200 troops that has served a peace-keeping function. The battling factions have agreed to demilitarize Ndjamena when the full African force is in place.

Western and African diplomats are skeptical about the proposed demilitarization's success.

"In the past, [the factions] would agree to leave, put on a show of marching out in the daytime and filter their combatants back into city at night," said a Western observer. "And I don't see how they are going to disarm the civilians."

Although the French have been peacekeepers since the major fighting ended a year ago, there is some anti-French sentiment among the Moslem factions for their role in supporting the overthrown southern-dominated government for many years.

Samtcho, one of a trickle of southerners to return to the capital, is a self-described bon vivant. He dresses in faddish track shoes, flared pants with his shirt unbuttoned to the navel and neck chain with gold pendant. He is self-assured, speaks French with smooth fluency and turns up his nose at the thought of Christianity, to which a minuscule number of other southerners adhere.

"I am an animist," a believer in traditional African religion, he said proudly.

Kaddi, modest and self-effacing, wears a white Moslem gown, the traditional heelless Arabic shoes and no jewelry, not even a watch. His Chadic Arabic is fluent, his French deliberate and slow. He is a fourth-generation Moslem from the precolonial Islamic kingdom of Baguirmi.

Ndjamena's social divisions were not evident to Samtcho when he first moved to the capital from his village of Kolon in Chad's southwest Tandjile Province in 1961, a year after Chad's independence from France.

Samtcho lived in the northerners' quarter with an uncle until 1963 when the southern-controlled government's harassment and excessive taxation of the Moslem community created tension between the two groups. Samtcho, with his uncle's family moved to Moursal, the southerners' part of Ndjamena.

The move "was precipitated by the political situation," he recalled. "We wanted to be away from the northerners. I see it today as part of the southern elite's dislike of the northerners."

The privileged son of a southern village chief, Samtcho graduated from high school in 1966 and went to work for the country's Customs Department until last February's fighting.

After fleeing south Feb 25, 1979, Samtcho returned north several times to Kousseri, the Cameroon border town directly across the Chari River boundary from Ndjamena. Each time he returned south after determining it was not safe yet for him in Ndjamena. He finally returned on Dec. 3.

Since returning, Samtcho has resumed his old job at the Customs Department and has experienced no difficulties.

Samtcho readily acknowledges that Chad's Moslem population -- which makes up at least half of the country's 4 million people -- have legitimate grievances, but he maintains that southerners should not be penalized because they are better educated.

In the Customs Department, where Samtcho assesses the value of imports for government taxes, 95 percent of the employes are black southerners, he said.

"Discrimination to me is when you pass the exam and you are not hired," said Samtcho. "The exam was equally given and those who were qualified were hired."

Within a year of Samtcho's move to the southerners' section of Ndjamena, Kaadi moved from his home town of Bousso to the capital. This was in 1964, when the separation between the two communities the men represent was complete.

Kaadi said he had started his secular education late. "My father did not want me to attend the local school since the teachers were Catholic" missionaries, he said. Instead, Kaadi was sent to the local Islamic school where he studied the Moslem holy book, the Koran, and learned Arabic script. w

"Life under the southerners was one of terror and submission to dictatorship," Kaadi said. "Personally, nothing happened to me, but my relatives were harassed and arrested for no reason."

After completing primary and secondary school (his father allowed him to attend when Chadian teachers replaced the missionaries), Kaadi was employed by Chad's Social Welfare Department as an investigator of accident claims. He said his employment made him increasingly bitter.

"I was treated badly at work," he said. "If you were not from the south you could not get scholarships for further study overseas or promotions." s

When fighting in Ndjamena broke out a year ago, Kaadi said he could not go to work and had to hide from government soldiers.

"The southerners went from house to house shooting Moslems, shooting us in the street," he said. "If you were wearing a Moslem gown, you were shot."

Now, southerner Samtcho says he sees "that the situation has changed and things will not be the same." Kaadi says it is "the victorious revolution that will ensure better treatment of the Moslems" in the future.

Both men, neither of whom knows the other, echo diplomatic observers' beliefs that Chad will not easily overcome the fractured politics of the past. b

"I am very pessimistic," said Samtcho, "about any peace in Chad."

"The problem is very delicate," echoed Kaadi. "The Moslems are . . . divided against themselves."