"Mauritania has hardly known colonization and has, therefore, neither suffered its ill effects nor realized its benefits. --Moktar Daddah, Mauritania's first president

More than two decades after making that observation tinged with cynicism about his country, Moktar Daddah reportedly enjoys a plush Parisian exile while the country he ruled autocratically for its first 18 years of independence lurches from crisis to crisis, torn by modern-day allegiances and the powerful grip of the past.

Sharply divided along ethnic and political lines, Mauritania may be one of Africa's worst examples of a country thrust into independence without even the rudiments of national cohesion. Its one unifying grace is the virtually universal adherance to Islam by its population of 1.4 million.

Conquered by the French in 1930 after a generation of warfare, Mauritania's fiercely independent Moorish warrior herdsmen were left alone in their harsh seasonal migrations with herds of cattle, sheep, goats and camels to follow the sparse rains. In the south, the black farmers along the north bank of the Senegal River pursued an unchanging life of subsistence agriculture.

In the centuries before colonial rule, both the Moors and the blacks developed rigid caste systems stratifying the people in descending order from warriors, Moslem holy men, herdsmen or farmers, craftsmen and, on the bottom rung, slaves. The two groups' contacts consisted of clashes during the old slave raids or exchanges of the herdsmen's milk for the farmers' grain.

Slave men, women and children tended the Moors' date fruit plantations in the scattered desert oases north of the river or tilled the fields of millet for the riverine blacks. The threat of starvation in this poor country keeps many aspects of the system of slavery operation in the same manner today, although the institution has been outlawed three times -- first by the French, then in 1960 by the independence constitution and again by the military government last year.

As a colony, Mauritania was ruled as a backwater appendage of France's West African colonial pearl, Senegal. It was unique among French colonies in not even having a central governmental administration until just before independence. The French dubbed the country of 400,000 square miles, 60 percent of which is covered by desert dunes, le vide -- the vacuum. By independence in 1960, Mauritania's society had undergone little change in its isolated state since the arrival of Islam with conquering Yemini Bedouin Arabs a thousand years before.

"What you see in Mauritania todayis a society in crisis," said a prominent Mauritanian journalist, who declined to be identified. "It is a society trying to form itself into a sense of nationhood while being jerked forward by modernism and pulled back by tradition."

After leading Mauritania to independence, Daddah was deposed in a bloodless Army coup in July 1978 for having entangled the country in an unwinnable war with Polisario guerrillas over control of the Western Sahara three years before. The new military government signed a peace treaty with Polisario in 1979.

Since taking power, the military government has been anything but stable, having overturned itself four times and reversing last April a 5-month-old program for return to civilian rule. In early 1979, nine months after taking power, the government quashed an internal "Pro-Algerian Marxist" takeover attempt.Last December, Libya was accused of trying to use its local supports to overthrow the government.

On March 16, a group of Mauritanian soldiers who had been living in exile in Morocco tried to overthrow the government in the country's first coup attempt that resulted in bloodshed. The fallout from that ended the country's brief experiment in civilian participation in government. The attempt seemed, in part, to reflect the strains between northern Moors, who dominate the military government, and southern Moors, who had easier access to power and influence under the deposed Daddah, also a southern Moor.

"One wonders, witht the poor economic state this country is in, what the perpetual power struggles are about," said a European aid official. "There is not much to go around."

Mauritania is a Sahelian country that, since the 1968-to-1974 drought in the region, has been able to grow only about a third of its annual food needs. The remainder, about 100,000 tons of cereals, is donated from abroad.

The drought also dramatically changed the country's demographics, severely straining the government's ability to provide services. In 1965, for example, 65 percent of the population led a self-sufficient, nomadic life. By the end of the drought, which wiped out entire herds, 65 percent of the population were sedentary farmers or had migrated to the cities seeking food and are still there.

The capital, Nouakchott, was a village of 500 people in 1957. Planned to house no more than 30,000 when selected as the government's administrative headquarters, it has grown to 200,000. The city is surrounded by a tent-and-shanty slum -- where at least 70 percent of the population lives -- built by poeple chased out of the Sahel's semiarid countryside by the drought.

Since the mid-1970s, the world market price for this country's major export, iron ore, has dropped from $25 a ton to $17 a ton, leaving for the government treasury a meager profit of $8 million after salaries and mining costs. The small $230 million annual budget suffered an $85 million deficit last year.

In only a generation of independence, six competitive conspiratorial political groups have evolved among the Mauritanian educated elite, a total of 15 percent of the population.

While everyone is Moslem, the Moors run the entire political gamut and look to the Arab world for political inspiration. The blacks are generally more conservative Francophiles.

Among the Moors, the groups include pro-Algerians, pro-Libyans, pro-Polisario and pro-Iraqis, the latter having created a small, growing Baathist Iraqi Moslem sect in Nouakchott. The blacks are pro-Moroccan and pro-Senegalan.

Presiding over all of this is the generally unflappable, good-humored military head of state, Lt. Col. Mohammed Khouna Haidalla, a 41-year-old desert Moor from northern Mauritania.

"It would be a mistake to underestimate Haidalla because of [his] humble demeanor," said one source who has frequent contact with him. "He has been quietly accumulating power since he was appointed" head of state by the 20-member military Committee for National Salvation.

In an interview, Haidalla said the brief participation of civilians in his government was ended because the March 16 coup attempt created too much instability. He denied that the apparent pro-Libyan leanings of the civilians had triggered their dismissal, but other Mauritanians and neutral observers argued that was the major factor.

Haidalla said the military committee "has decided to lead Mauritania into democracy itself," but no timetable has been given.

Haidalla disagreed with some observers' views that Mauritania is a society divided against itself. "To the contrary," he said, "past and recent history in Mauritania confirms that each time there is something that disturbs the independence, soverignty and integrity of Mauritania, the Mauritanians' attachment to their country has never been absent."