The agogo comes originally from Nigeria in West Africa. It is a sort of conical iron bell without any clapper, and it is struck with a metal rod. It originates from the Yoruba tribe, and is used to accompany all kinds of music in the Yoruba regions of Nigeria. 

This instrument must have been taken to the Americas by the slaves transported from West Africa, because a similar instrument is also used today in Brazil, to accompany samba music.  Modern versions of the agogo have quite widespread use in the percussion kits of popular, folk and rock music bands.