The Merina, whose name means "those from the country where one can see far" (an eloquent yet important reference to their control of the central highlands) are not only the most numerous of the Malagasy peoples, representing more than one-quarter of the total population (26.2 percent), but since the early nineteenth century have been the most organized in terms of social, economic, and political structure. During the nineteenth century, the Merina almost succeeded in unifying the entire island under a centralized administration. Although their influence declined somewhat during the French colonial period, especially after the unsuccessful Revolt of 1947, they are heavily represented among the country's socioeconomic and political elite. Merina territory originally consisted only of the lands encircling the current capital of Antananarivo, but as they expanded in the eighteenth and nineteenth centuries, it came to include most of the northern central highlands, now the province of Antananarivo. Many Merina have settled in other parts of the island as government officials, professionals, and traders, and all the major cities have sizable Merina populations.

The Merina are considered the most "Asian" of the Malagasy ethnic groups in terms of their physical characteristics and culture. Having relatively light complexions and straight black hair, as well as a way of life based on wet-rice cultivation, they are strongly reminiscent of the peoples of Southeast Asia. It has been suggested that the ancestors of the Merina may have preserved their Malayo-Indonesian characteristics through the practice of endogamy or intermarriage. Such a practice would have discouraged their marrying with African peoples even during their hypothesized sojourn on the East African coast, which may have lasted centuries. The plausibility of this thesis is supported by the fact that the Merina continue to practice endogamy, although it is also plausible that Merina ancestors may simply have migrated directly to Madagascar without settling first in Africa. The Merina are sensitive to physical differences and distinguish between people who are fotsy (white), with relatively light complexions and descended from the freeborn of the nineteenth-century Merina kingdom, and those who are mainty (black), descendants of slaves or captives from other parts of the island who are described as being more "African" in physical appearance. Fotsy and mainty are not always clearly distinguishable, even to the Merina themselves, but this racial distinction nonetheless divides Merina society into two distinct groups and contributes to its highly unequal nature.

The Betsileo, who constitute 12.1 percent of the population and live in the central highlands south of the Merina in a region of about 40,000 square kilometers, have a culture similar to that of their northern neighbors. They are reputedly the best farmers in Madagascar, building rice terraces on the slopes of steep hills similar to those of Indonesia or the Philippines. They were united in the late eighteenth century by975 by King Andriamanalimbetany of Isandra, one of the four Betsileo royal principalities, but were incorporated into the Merina kingdom in 1830. The Betsileo share something of the privileged position of the Merina, constituting a significant portion of Madagascar's official, professional, and skilled artisan classes.

South of the Betsileo live the Bara (3.3 percent of the population), who are divided into five clans in the dry regions at the southern end of the central highlands. They keep large herds of zebu cattle and are the most pastoral people in Madagascar they also have a reputation of being valiant warriors.

The Tsimihety (7.3 percent of the population), whose lands are located north of Imerina, illustrate rather strikingly the birth and development of a Malagasy people. Their name, "those who do not cut their hair," refers to the refusal of their forebears in the early eighteenth century to submit to the Sakalava custom of cutting their hair when the king died rather, they migrated to the unsettled north-central region of the island. The Tsimihety are noted for the rapid expansion of their population and for their penchant for migration, expanding the boundaries of their territory and encroaching on the lands of neighboring peoples. Primarily raisers of cattle, they are divided into a large number of traditional clans with little political organization. They are described as the individualists of the island, desiring to live a life free of government control in the unsettled hinterlands.

Data as of August 1994