Chari River in the context of "Ubangi-Shari"

The Central African Republic (CAR) is a landlocked country in Central Africa. It is bordered by Chad to the north, Sudan to the northeast, South Sudan to the east, the Democratic Republic of the Congo to the south, the Republic of the Congo to the southwest, and Cameroon to the west. Bangui is the country's capital and largest city, bordering the Democratic Republic of the Congo. The Central African Republic covers a land area of about 620,000 square kilometres (240,000 sq mi). As of 2024, it has a population of 5,357,744, consisting of about 80 ethnic groups, and is in the scene of a civil war, which has been ongoing since 2012. Having been a French colony under the name Ubangi-Shari, French is the official language, with Sango, a Ngbandi-based creole language, as the national and co-official language.

The Central African Republic mainly consists of Sudano-Guinean savanna, but the country also includes a Sahelo-Sudanian zone in the north and an equatorial forest zone in the south. Two-thirds of the country is within the Ubangi River basin (which flows into the Congo), while the remaining third lies in the basin of the Chari, which flows into Lake Chad.

The Nilo-Saharan languages are a proposed family of around 210 African languages spoken by somewhere around 70 million speakers, mainly in the upper parts of the Chari and Nile rivers, including historic Nubia, north of where the two tributaries of the Nile meet. The languages extend through 17 nations in the northern half of Africa: from Algeria to Benin in the west; from Libya to the Democratic Republic of the Congo in the centre; and from Egypt to Tanzania in the east.

As indicated by its hyphenated name, Nilo-Saharan is a family of the African interior, including the greater Nile Basin and the Central Sahara Desert. Most of its proposed constituent divisions are found in the modern countries of Sudan and South Sudan, through which the Nile River flows.

Lake Chad (Arabic: بحيرة تشاد, Kanuri: Sádǝ, French: Lac Tchad) is an endorheic freshwater lake located at the junction of four countries: Nigeria, Niger, Chad, and Cameroon, in western and central Africa respectively, with a catchment area in excess of 1,000,000 km (390,000 sq mi). It is an important wetland ecosystem in West-Central Africa. The lakeside is rich in reeds and swamps, and the plain along the lake is fertile, making it an important irrigated agricultural area. The lake is rich in aquatic resources and is one of the important freshwater fish producing areas in Africa.

Lake Chad is divided into deeper southern parts and shallower northern parts. The water source of the lake mainly comes from rivers such as the Chari River that enter the lake. The water level varies greatly seasonally, and the area of the lake also changes dramatically. During the African humid period, the lake's area reached 400,000 km (150,000 sq mi). Due to the increasingly arid climate, the lake surface gradually shrank. In the 19th century, it still had an area of 28,000 km (11,000 sq mi). However, due to climate change and human water diversion, it has shrunk significantly since the mid-1970s, and its area has fluctuated between 2,000 and 5,000 km (770 and 1,930 sq mi).

The Ubangi River (/(j)uːˈbæŋɡi/; Swahili: Mto Ubangi; French: Fleuve Oubangui; Dutch: Mubangi Stroom), also spelled Oubangui, is a river in Central Africa, and the largest right-bank tributary of the Congo River. It begins at the confluence of the Mbomou (mean annual discharge 1,350 m/s) and Uele Rivers (mean annual discharge 1,550 m/s) and flows west, forming the border between Central African Republic (CAR) and the Democratic Republic of the Congo (DRC). Subsequently, the Ubangi bends to the southwest and passes through Bangui, the capital of the CAR, after which it flows south – forming the border between the DRC and the Republic of the Congo. The Ubangi finally joins the Congo River at Liranga.

The Ubangi's length is about 1,060 km (660 mi). Its total length with the Uele, its longest tributary, is 2,270 km (1,410 mi). The Ubangi's drainage basin is about 651,915 km (251,706 sq mi). Mean annual discharge at mouth 5,936 m/s. Its discharge at Bangui ranges from about 800 m/s (28,000 cu ft/s) to 11,000 m/s (390,000 cu ft/s), with an average flow of about ~4,000 m/s (140,000 cu ft/s). It is believed that the Ubangi's upper reaches originally flowed into the Chari River and Lake Chad before being captured by the Congo in the early Pleistocene.

The Sao civilization (also called So) flourished in Central Africa from the 6th century BCE or 5th century BCE, to as late as the 16th century AD. The Sao lived by the Chari River basin in territory that later became part of Cameroon and Chad. They were the earliest civilization to have left clear traces of their presence in the territory of modern Cameroon. Sometime around the 16th century, conversion to Islam changed the cultural identity of the former Sao. Today, several ethnic groups of northern Cameroon and southern Chad, but particularly the Sara and Kotoko, claim descent from the civilization of the Sao.