JOHANNESBURG — Alex Okosi might not have single-handedly launched Viacom’s Africa operations, but for more than a decade the executive VP and managing director of VIMN Africa has been the driving force behind the company’s continent-wide expansion. Okosi spearheaded the rollout of local brands like MTV Base and BET Africa, while overseeing a portfolio of Viacom properties that reaches more than 100 million viewers across pay-TV, FTA, SVOD and mobile platforms. Since the start, the Nigerian-born taste-maker has touted the untapped potential of the continent’s expanding middle class, powering VIMN Africa to become Viacom’s fastest-growing international operation in terms of revenues. On a continent where more than half the population is under the age of 20, he’s an outspoken evangelist for the all-important youth demo, developing content that’s meant to empower as much as entertain. After being tapped this year to lead BET International in all markets outside the U.S., Okosi will now showcase his talents on the global stage.