Karl Klans Von Der Decken, a German traveller, born at Kotzen, Prussia, Aug. 8, 1833, killed at Berderah, E. Africa, Oct. 3, 1865. He entered the Hanoverian army in 1850, but left the service in 1860, having begun his travels in Africa as early as 1857. In May, 1861, he set out to explore the lake country of eastern Africa, and returned to Zanzibar Dec. 31, 1862, having made the ascent of Mount Kilimanjaro to the height of 13,000 ft. In May, 1863, he made explorations on the coast, after which he returned to Europe. In October, 1864, he went again to Zanzibar, with two steamers constructed at his own expense in Hamburg.

In August, 1865, he commenced the ascent of the river Juboo, in company with several other travellers. They were attacked on Oct. 1 by the natives, and forced to take refuge in boats, Decken and Dr. Link, a physician of Berlin, losing their lives. The results of his explorations have been given by Kersten in Reisen in Ostafrika in den Jahren 1859-'65 (4 vols., Leipsic, 1869-'71).