I suspect Africa is a big place (never made it there) , with different cultural influences, and history:)
But, consider this quote....which relates to the influence of Christianity and colonization on at least some of Africa:

"....an African tradition of homosexuality can be found if you know where to look. There is a lot of data ( on that) as well as proof from our languages. When the Christians came, they demonized it. In Uganda, Father Lourdel from France brainwashed our forefathers by teaching them that homosexuality is evil. They had no problem with it before that. The British came later and criminalized it. It was not an issue before that. By doing this both the European Christians and colonialists brought homophobia to a continent that was clean of it. Africa embraced it and everything that the 'masters' brought. To date we still suffer the effects. It makes me sick that our leaders know about this history and yet they will go ahead and make such misleading remarks. We need to remind them of that history."

Victor Juliet Mukasa, activist with the International Gay and Lesbian Human Rights Commission (IGLHRC), focusing on the East, Central and Horn regions of Africa.

http://www.xtra.ca/public/National/Out_in_Africa-7002.aspx