Claim: The first PM of Sierra Leone was Sir Milton Margai.

Sierra Leone -LRB- -LSB- sɪˈɛərə_lɪˈəʊni , _ - lɪˈəʊn -RSB- -RRB- , officially the Republic of Sierra Leone , is a country in West Africa . It is bordered by Guinea to the north-east , Liberia to the south-east , and the Atlantic Ocean to the south-west . Sierra Leone has a tropical climate , with a diverse environment ranging from savannah to rainforests . Sierra Leone has a total area of 71740 km2 and a population of 7,075,641 -LRB- based on 2015 national census -RRB- .   Sierra Leone is officially made up of four administrative regions : the Northern Province , Eastern Province , Southern Province and the Western Area , which are subdivided into fourteen districts . Each district has its own elected local government .   Freetown -LRB- population 1,050,301 -RRB- , located in the Western Area , is the capital , largest city and its economic and political centre . Bo -LRB- population 306,000 -RRB- , is the second largest city , and is located in the Southern Province , about 160 miles from Freetown . Kenema -LRB- population 200,354 -RRB- , located in the Eastern Province , is the third largest city and is about 190 miles from Freetown . Koidu Town -LRB- population 128,074 -RRB- , located in the diamond rich Kono District in the Eastern Province , is the fourth largest city , and is about 275 miles from Freetown . Makeni -LRB- population 126,058 -RRB- , located in the Northern Province , is the fifth largest of Sierra Leone 's five major cities , and is about 85 miles from Freetown .   Sierra Leone is a constitutional republic with a directly elected president and a unicameral legislature . Sierra Leone became an independent Nation on 27 April 1961 from Britain , led by Sir Milton Margai , who was elected by landslide as the first prime minister of the new nation under parliamentary government .   The current constitution of Sierra Leone was adopted in 1991 during the presidency of Joseph Saidu Momoh , though it has been amended several times . Since independence to present , Sierra Leone politics has been dominated by two major political parties ; the Sierra Leone People 's party -LRB- SLPP -RRB- and the All People 's Congress -LRB- APC -RRB- . The current president of SIerra Leone is Ernest Bai Koroma , a member of the APC party , who was elected in 2007 after defeating the ruling SLPP candidate , and he won reelection for his final term as president in 2012 .   From 1991 to 2002 , the Sierra Leone civil war was fought and devastated the country . This proxy war left more than 50,000 people dead , much of the country 's infrastructure destroyed , and over two million people displaced as refugees in neighbouring countries . In January 2002 , then Sierra Leone 's president Ahmad Tejan Kabbah , fulfilled his campaign promise by ending the civil war , with help by the British Government , ECOWAS and the United Nations .   More recently , the 2014 Ebola outbreak overburdened the weak healthcare infrastructure , leading to more deaths from medical neglect than Ebola itself . It created a humanitarian crisis situation and a negative spiral of weaker economic growth . The country has an extremely low life expectancy at 57.8 years .   About sixteen ethnic groups inhabit Sierra Leone , each with its own language and customs . The two largest and most influential are the Temne and the Mende people . The Temne are predominantly found in the north of the country , while the Mende are predominant in the south-east . Sierra Leone has a significant minority of the Krio people , who are descendants of freed African American and West Indian slaves .   Although English is the official language spoken at schools and government administration , the Krio language is the most widely spoken language across Sierra Leone and is spoken by 97 % of the country 's population . The Krio language unites all the different ethnic groups in the country , especially in their trade and social interaction with each other .   Sierra Leone is a predominantly secular Muslim majority country , with the overall muslim population at 77 % of the population , though with an influential Christian minority at about 22 % . Sierra Leone is regarded as one of the most religiously tolerant nations in the world . Muslims and Christians collaborate and interact with each other very peacefully . Religious violence is very rare in the country . The major Christian and Muslim holidays are officially national holidays including Christmas and Eid Al Fitr . In politics , the overwhelming majority of Sierra Leoneans vote for a candidate without regard to whether the candidate is a Muslim or a Christian .   Sierra Leone has relied on mining , especially diamonds , for its economic base . It is also among the largest producers of titanium and bauxite , a major producer of gold , and has one of the world 's largest deposits of rutile . Sierra Leone is home to the third-largest natural harbour in the world . Despite exploitation of this natural wealth , 70 % of its people live in poverty .   Sierra Leone is a member of many international organisations , including the United Nations , the African Union , the Economic Community of West African States -LRB- ECOWAS -RRB- , the Mano River Union , the Commonwealth of Nations , the African Development Bank , and the Organisation of Islamic Cooperation .