Tanga was chosen in 1889 as a military post of German East Africa, and became a district office in 1891. The local economy was based on sisal, which had been brought to the colony several years earlier, and population in the area grew rapidly. The town was also established as the terminus of the Usambara railway line, which runs inland to Moshi at the foot of Kilimanjaro.
As the coastal town closest to Kenya, Tanga was on the front line at the outset of World War I. A British landing was thrown back on 4 November 1914 in the Battle of Tanga, and the town was not taken until 7 July 1916.
In Spanish, a Tanga is the name people use to refer to a tonge panty. Tangas are fairly popular in Latin American beaches and on some television shows.