Liberia , officially the Republic of Liberia, is a country in West Africa bordered by Sierra Leone to its west, Guinea to its north and Ivory Coast to its east. It covers an area of and is home to about 4 million people. English is the official language; 15 indigenous languages are also spoken within Liberia. Its coastline is composed mostly of mangroves, while its more sparsely populated inland consists of forests opening onto a plateau of drier grasslands. The climate is hot and equatorial, with significant rainfall during the May–October rainy season and harsh harmattan winds the remainder of the year. Liberia possesses about forty percent of the remaining Upper Guinean rainforest. Liberia was founded by the United States while occupied by local Africans. Beginning in 1820, the area was settled by African Americans, most of whom were freed slaves. African captives freed from slave ships by the British and Americans were sent to Liberia instead of being repatriated to their various African countries of origin. The colonists established a new country with the help of the American Colonization Society, a private organization whose leaders thought former slaves would have greater opportunity in Africa and that the Black population in the United States would remain a permanent racial underclass. In 1847, this new country became the Republic of Liberia, establishing a government modeled on that of the United States and naming its capital city Monrovia after James Monroe, the fifth president of the United States and a prominent supporter of the colonization. The colonists and their descendants, known as Americo-Liberians, led the political, social, cultural and economic sectors of the country and ruled the nation for over 130 years as a dominant minority. Liberia began to modernize in the 1940s following investment by the United States during World War II and economic liberalization under President William Tubman. Liberia was a founding member of the United Nations and the Organisation of African Unity. In 1980 a military coup overthrew the Americo-Liberian leadership after 150 years of power, marking the beginning of political and economic instability and two successive civil wars. These resulted in the deaths of between 250,000 and 520,000 people and devastated Liberia’s economy. A peace agreement in 2003 led to democratic elections in 2005. Today, about 85% of the population live below the international poverty line. Liberia’s economic and political stability has recently been threatened by a deadly Ebola virus epidemic which originated in Guinea in December 2013 and entered Liberia in March 2014.