english is an african language

The English language is not confined to England of course:

Jay Doubleyou: "let’s not make english about british culture"

And, of course, English speakers are not only born in England:

Jay Doubleyou: native speakerism

They are also born, for example, in Africa:

Jay Doubleyou: the english-speaking world: west africa

It's considered 'an African language':

English is already becoming the language of the African continent as we speak:

English is an African Language- the Language of Coexistence - Mulosige 

It's complicated of course:

Nigeria’s relationship to the English language, like that of all English-speaking African nations, is a complicated one. Chinua Achebe – one of the legends – wrote of the English language, “we may go on resenting it, because it came as part of a package deal that included many other items of doubtful value, especially the atrocities of racial arrogance and prejudice which may yet set the world on fire … If [English] failed to give them a song it at least gave them a tongue for sighing.”

Africa’s colonisation of the English language continues apace | Afua Hirsch | The Guardian

And there is a healthy debate going on:

Ngugi Wa Thiong'o: English is not an African language - BBC News

But it seems that those outside Africa need to be reminded that Africans speak English:

English is the official language of Nigeria, and both in the country’s colonial era and since independence from Britain in 1960, it has been the country’s standard language of instruction. To be a Nigerian college student typically means to have been studying in English at least since the start of elementary school. And although many U.S. and Canadian universities do exempt students from Nigeria and other Anglophone countries from such tests, not all do.

English Speakers From Africa Face Discrimination in the West

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