While many of the musical characteristics of Gospel can be directly linked to African cultural music, like the strong vocals with a very clear use of positive harmonies, the content of most songs contain more spiritual and cultural lyrics rather then directly referring to the bible (to be quite general) or direct religious stories. The clear African connection emerges when thinking about another name Gospel music receives in the US - Black Gospel. This is to differentiate it from other Christian music, clearly stating its African roots.
It is though that first ever publicly known Gospel song (as per today's definition) appeared in 1874 in the US by Philip Bliss, called "Gospel Song". One of the most prominent African contemporaries of Gospel Music is clearly the Soweto Gospel Choir. For global representatives of Gospel Music, see the Gospel Hall of Fame. See now a beautiful African Gospel song, performed by a great South African Youth Choir, led by Siyabonga Cele.