the Huapí Mountains, and the Yolaina Mountains. Climate In central Nicaragua, the temperature varies between ; rainfall averages per year. There is a four-month dry season, with the rain season lasting throughout the rest of the year. Before the conquest, the Central Highlands were covered with coniferous forest. The Pacific coastal plain is classified as tropical dry forest, and features fertile volcanic soils. The Atlantic lowlands receive higher rainfall; the soils are less fertile, and the region is classified as tropical moist forest. Nicaragua before the conquest When the Spanish first arrived in what is now Nicaragua there were three principal indigenous groups living in the western portions of the country; these were the Chorotega (also known as the Mangue), the Nicarao, and the Matagalpa (also known as Chontal, from the Nahuatl term for "foreigner"). The Nicarao were a Nawat-speaking Mesoamerican people that had migrated southwards from central Mexico from the 8th century AD onwards. They broke off from the Pipil around the early 13th century and settled in pockets of western Nicaragua along the Pacific coast, with their heaviest concentration in what is now the department of Rivas. The Chorotega were also a Mesoamerican people that had migrated from Mexico and spoke the Mangue language. The Subtiaba (also known as the Maribio) were another group of Mexican origin, speaking the Subtiaba language. The Tacacho were a small group of unknown origin and language. The Matagalpa were a non-Mesoamerican people of the Intermediate Area, who spoke a Misumalpan language, but belonged to the Chibchoidean cultural region. They occupied the Central Highlands, over an area covering the modern departments of Boaco, Chontales, Estelí, Jinotega, Matagalpa, southwestern parts of Nueva Segovia, and neighbouring parts of Honduras. The Matagalpa were a tribal society organised into different lineages and chiefdoms, who engaged in organised intertribal warfare; at the time of Spanish contact they were at war with the Nicarao. Eastern Nicaragua was inhabited by Chibchoidean peoples such as the Rama, and the Misumalpa peoples such as the Mayangna and the Miskito. The Chibchoidean peoples of the interior were culturally related to South American groups, and had developed more complex societies than that of the Miskito, who were of Caribbean origin. The population of Nicaragua at the time of contact is estimated at 825,000. The first century after Spanish contact witnessed the demographic collapse of the native populations, resulting principally from exposure to Old World