The Sonjo are a people living in northern Tanzania

Tanzania

The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

, 30-40 miles west of Lake Natron

Lake Natron

Lake Natron is a salt lake located in northern Tanzania, close to the Kenyan border, in the eastern branch of Africa's Great Rift Valley. The lake is fed by the Ewaso Ng'iro River but also by mineral-rich hot springs and is quite shallow, less than three meters deep, and varies in width depending...

, who have lived for centuries as an isolated enclave in Maasai territory. In 2002 the Sonjo population was estimated to number 30,000 (Ethnologue). They are known for their use of a traditional irrigation system in farming, a practice which has led some historians to link them to the hitherto unexplained ruined irrigation systems of Engaruka

Engaruka

Engaruka is an abandoned system of ruins in the Great Rift Valley of northern Tanzania , famed for its irrigation and cultivation system. It is considered one of the most important Tanzanian archaeological sites.-Site:...

, 60 miles to the southeast. The term Sonjo is the name given to the people by the Maasai; they call themselves Batemi and their language

Sonjo language

Sonjo is a Bantu language spoken in northern Tanzania, 30–40 miles west of Lake Natron. Ethnolinguistically, it is a displaced member of Guthrie’s E50 group, most other members of which are found in Central Kenya. Within that group, it is most closely related to Gikuyu...

Ketemi or Gitemi.