15,000,000 in Tanzania (2012), increasing. Population total all countries: 15,457,390.
Formerly Zanzibar, coastal areas. Now widespread. Also in Burundi, Canada, Kenya (Kiswahili), Libya, Mozambique, Oman, Rwanda, Somalia, South Africa, Uganda, United Arab Emirates, United States.
1 (National). De facto national language.
Mgao, Mrima, Pemba, Unguja (Kiunguja, Zanzibar). Lexical similarity: Bajun dialect 85% with the Amu dialect, 78% with the Mvita dialect, 72% with the Mrima dialect; Mvita dialect 86% with Amu, 79% with Mrima; Mrima dialect 79% with Amu.
Probably over 80% of rural people are L2 users; they use the local language for most activities, but Swahili [swh] with outsiders. It is also common for people of numerous ethnic groups to speak Swahili as L1, especially in urban and very mixed areas. All domains. All ages. Positive attitudes.
Muslim, Christian, traditional religion.