The explosion of Catholicism in sub-Saharan Africa during the 20th century ranks among the greatest missionary success stories in church history. From a Catholic population of 1.9 million in 1900, the total for sub-Saharan African mushroomed to 139 million in 2000, a staggering growth rate of 6,70 percent. Moreover, almost half of the adult baptisms in global Catholicism occur in Africa, meaning that the growth of the church has been driven not merely by overall demographic trends but also by success in attracting new converts.

By 2050, three African nations will rank among the ten largest Catholic countries on earth: the Democratic Republic of the Congo (97 million Catholics), Uganda (56 million) and Nigeria (47 million). The traditional Catholic powerhouses of Spain and Poland, meanwhile, are projected to drop off the list.