The Scholar Who Raised a CaliphateHausaland · 1804–1808“Sometimes the revolution begins not with a sword, but with a sermon.”Usman dan Fodio was a teacher. For years he preached in the Hausa kingdoms against corrupt rule and crooked taxes, and for years the kings tolerated him — until Gobir's King Yunfa decided a popular scholar was more dangerous than an army, and moved against him.The lesson the elders kept: A reform movement that wins must become a state — and the state it builds may outlive even its conquerors' intentions.