41. David Livingstone

Just as William Carey had opened the doors for missionary labor in India, David Livingstone paved the way into the interior of Africa with a similar vision. His lifelong, lonely quest produced an explosion of knowledge of the 'dark' continent, and made Livingstone one of the most celebrated men of his age. From his own perspective, however, his objective was straightforward. He only wished to see in the wake of his efforts hundreds more missionaries who would establish in Africa a Christian presence that would spread the gospel, and drive out the horrific abuses of the slave trade that dominated the African world.