May 18, 1291: The last Christian territory taken by the Crusaders, Acre, falls to the Sultan of Egypt (see issue 40: The Crusades).
May 18, 1834: Sheldon Jackson, Presbyterian missionary to the frontier West and Alaska, is born in Minaville, New York. Jackson's reputation for ministering to the spiritual, physical, and social needs of both natives and settlers earned him the nicknames "Bishop of All Beyond" and "Apostle to Alaska" (see issue 66: How the West Was Really Won).
August 3, 1492: Christopher Columbus sets sail from Spain for the "Indies." Though the explorer was in part driven by a quest for gold and glory, he also saw himself as a missionary. He thought, if there were a shortcut to the East by sea, missionaries could be sent there faster, thus enabling Christians to meet the provision for world evangelization before the Lord could return (see issue 35: Christopher Columbus).