The Anglo-Zanzibar War is listed in the Guinness Book of World Records as the shortest war in all of officially recorded history. This conflict lasted a total of 38 minutes, and was fought between the United Kingdom and the now defunct Sultanate of Zanzibar on August 27, 1896.
The conflict between the two nations was triggered at the death of the erstwhile Sultan of Zanzibar, Hamad bin Thuwaini, on August 25, 1896. Thuwaini had been extremely favorable to British interests in the region, and had reigned as more or less of a client king at the pleasure of the Empire. Thuwaini was succeeded as Sultan by Khalid bin Barghash, a ruler who was viewed as much less favorable to the interests of Great Britain.
The two nations had previously signed a treaty that stated the Sultanate would pass into the hands of Hamud bin Muhammed, who was favored by the British. Barghash was thus viewed as a usurper. The British sent an ultimatum to Barghash, instructing him to surrender the throne immediately in favor of Muhammed. Barghash refused, and barricaded himself inside his palace.
The ultimatum expired on August 27, at which time the British sent troops to bombard the palace. The conflict lasted 38 minutes, at the end of which Barghash surrendered, Muhammed was installed as Sultan, and the world’s shortest war came to an end. The total number of wounded or killed on the Zanzibar side was listed as 500, while the British reported the wounding of one sailor.