Monrovia is Liberia's cultural, political and financial hub. The body that administers the government of Greater Monrovia District is the Monrovia City Corporation.

Founded in 1822, Monrovia was the first permanent Black American settlement in West Africa. Monrovia's economy is dominated by its harbour and as the location of Liberia's government offices.

Monrovia is named in honor of U.S. President James Monroe, a prominent supporter of the colonization of Liberia. Along with Washington, D.C., it is one of two national capitals to be named after a U.S. President.

In 1816, with the aim of establishing a self-sufficient colony for emancipated American survivors of slavery, something that had already been accomplished in Freetown, the first settlers arrived in Africa from the United States, under the auspices of the American Colonization Society. They landed at Sherbro Island in present-day Sierra Leone. The undertaking was a shambles and many settlers died.

In 1822, a second ship rescued the settlers and took them to Cape Mesurado, establishing the settlement of Christopolis. In 1824, the city was renamed to Monrovia after James Monroe, then President of the United States, who was a prominent supporter of the colony in sending freed Black slaves to Liberia and who saw it as preferable to emancipation in America.

In 1845, Monrovia was the site of the constitutional convention held by the American Colonization Society which drafted the constitution that would two years later be the constitution of an independent and sovereign Republic of Liberia.

At the beginning of the 20th century, Monrovia was divided into two parts: (1) Monrovia proper, where the city's Americo-Liberian population resided and was reminiscent of the Southern United States in architecture; and (2) Krutown, which was mainly inhabited by ethnic Krus but also Bassas, Grebos and other ethnicities. Of the 4,000 residents, 2,500 were Americo-Liberian. By 1926, ethnic groups from Liberia's interior began migrating to Monrovia in search of jobs.

In 1979, the Organisation of African Unity held their conference in the Monrovia area, with then president William R. Tolbert as chairman. During his term, Tolbert improved public housing in Monrovia and decreased by 50% the tuition fees at the University of Liberia. A military coup led by Samuel Doe ousted the Tolbert government in 1980, with many members being executed.

The city was severely damaged in the First and Second Liberian Civil Wars, notably during the siege of Monrovia, with many buildings damaged and nearly all the infrastructure destroyed.

 Major battles occurred between Samuel Doe's government and Prince Johnson's forces in 1990 and with the NPFL's assault on the city in 1992. A legacy of the war is a large population of homeless children and youths, either having been involved in the fighting or denied an education by it.

In 2002, Leymah Gbowee organized the Women of Liberia Mass Action for Peace with local women praying and singing in a fish market in Monrovia.[8] This movement helped bring an end to the Second Liberian Civil War in 2003 and the election of Ellen Johnson Sirleaf in Liberia, the first African nation with a female president.

As of September 2014, an ongoing Ebola epidemic has been affecting the city.

Monrovia lies along the Cape Mesurado peninsula, between the Atlantic Ocean and the Mesurado River, whose mouth forms a large natural harbor. The Saint Paul River lies directly north of the city and forms the northern boundary of Bushrod Island, which is reached by crossing the "New Bridge" from downtown Monrovia. 

Monrovia is located at 6°19′N 10°48′W. Monrovia is Liberia's largest city and its administrative, commercial and financial center.

The city is located in Montserrado County. The small town of Bensonville is actually the capital of Montserrado County.

Under the Köppen climate classification, Monrovia features a tropical monsoon climate (Am).During the course of the year Monrovia sees a copious amount of precipitation. Monrovia averages 5,100 mm (200 in) of rain per year. In fact, Monrovia is the wettest capital city, receiving more annual precipitation on average, than any other capital in the world.

The climate features a wet season and a dry season, but precipitation is seen even during the dry season. Temperatures remain constant throughout the year averaging around 26 °C (79 °F).