| Official Name: | Gabu |
| Other Name: | Nova Lamego |
| Native Name: | Gabu |
| Pushpin Map: | Guinea-Bissau#Africa |
| Pushpin Label Position: | bottom |
| Pushpin Mapsize: | 320 |
| Pushpin Map Caption: | Location in Guinea-Bissau |
| Subdivision Type: | Country |
| Subdivision Name: | Guinea-Bissau |
| Subdivision Type1: | Region |
| Subdivision Name1: | Gabu Region |
| Subdivision Type2: | District |
| Population As Of: | 2010 |
| Population Total: | 37525 |
| Population Density Km2: | auto |
| Population Blank1 Title: | Ethnicities |
| Population Blank1: | Mandinka, Fula |
| Population Blank2 Title: | Religions |
| Population Blank2: | Islam |
| Coordinates: | 12.2833°N -14.2167°W |
| Elevation M: | 39 |
Gabu is the largest town in eastern Guinea-Bissau and capital of the Gabu Region. Under the name Kansala, it was the capital of Kaabu.
Kaabu, also written Ngabou or N’Gabu, was founded by Mandinka immigrants from the Mali Empire in the 13th century, and was initially vassal to the Mali Empire. Mansa Sala Sane established Kansala to replace the old, less centrally located Bainuk capital of Mamapatim. The city was also the site of the sacred grove where the mansaba of Kaabu was crowned.[1] As the Mali empire waned, Sama Koli proclaimed independence in 1537 but maintained many of the trappings of Malian cultural heritage. The kingdom built earthen ramparts (now vanished) around Kansala and established trade relations with the Portuguese on the coast.[2]
In the early nineteenth century, the Fula ethnic group converted to Islam and began the Kansala War to end Mandé dominance. It ended with a big fire which caused extensive damage and casualties on both sides. Gabu thereafter became linked with the Imamate of Futa Jallon and was finally assimilated into the Portuguese Empire.[2] The Portuguese named the town "Nova Lamego" ie "New Lamego", after the Douro town of Lamego. It was renamed Gabu (sometimes spelled Cabu[3]) after Guinea Bissau's independence.
Gabu is now mostly known as a market town with the second largest market of Guinea-Bissau, notably trading coal and ceramics as well as agricultural products. Traders come from as far afield as Guinea and Senegal.
Gabú has a tropical savanna climate (Köppen Aw), similar to that of the capital Bissau but with – due to its inland location – about a quarter less rainfall and larger diurnal temperature variations. As with all of Guinea-Bissau, there are two extremely contrasting seasons: a dry season from November to May with dusty harmattan winds and hot to sweltering, rainless weather, and a monsoonal wet season from June to October featuring heavy thunderstorm rains almost every day and hot, uncomfortably humid conditions.