William Lewis Sachtleben (March 29, 1866 in Alton, Illinois – December 13, 1953 in Fort Lauderdale, Florida) was a 19th-century American journalist and lecturer who was one of the early globe-circling bicyclists, at one time holding a world record for long-distance bicycling.

His attempt in 1895 to rescue, recover, and achieve justice for fellow cyclist Frank Lenz, who had disappeared in Turkey (then in the Ottoman Empire) at the time of the Hamidian Massacres,[1] was seen as akin to the earlier search for David Livingstone in Africa.

He sailed to Europe in March 1895, and traveled to Erzurum, having to forge papers to gain entrance to Ottoman Kurdistan.

In Erzurum, Sachtleben learned that Lenz had somehow insulted a notorious local Kurdish chief when passing through a small village there.

Some of the Armenian locals who had helped Sachtleben uncover Lenz' fate were also imprisoned, a couple of them dying in prison.