Originating on Bourbon Island (now called Reunion Island) in the Indian Ocean off the East Coast of Africa, the process for producing the best vanilla beans in the world now refers to beans grown and cured on Reunion itself and the nearby islands: Madagascar and the Comoros Islands.
By far the most important of these is Madagascar, which produces more than 60% of the world's vanilla, and where these finest of vanilla beans, known as Bourbon vanilla beans come from. Agricultural map of Madagascar.