Portuguese language in Africa as a second language, in countries like Angola and Mozambique, where Portuguese is an official language, but also in countries like South Africa and Senegal, thanks to migrants coming from Portuguese speaking countries. Some statistics claim that there are over 30 million Portuguese speakers in the continent. Like French and English, Portuguese has become a post-colonial language in Africa and one of the working languages of the African Union (AU) and the Southern African Development Community (SADC). Portuguese co-exists in Guinea-Bissau, Cape Verde, and São Tomé and Principe with Portuguese-based creoles (Upper Guinea and Gulf of Guinea Creoles), and in
South West Africa land taken from the northern border of Bechuanaland, extending as far as the Zambezi river, was added to the colony. It was named the Caprivi Strip ("Caprivizipfel") after the German Chancellor Leo von Caprivi. In 1915, during South West Africa Campaign of World War I, South Africa captured the German colony. After the war, it was declared a League of Nations Class C Mandate territory under the Treaty of Versailles, with the Union of South Africa responsible for the administration of South West Africa. From 1922, this included Walvis Bay, which, under the South West Africa Affairs Act, was governed