John Oxenham
John Oxenham (a.k.a. "John Oxnam", died September 30, 1580) was the first non-Spanish European explorer to cross the Isthmus of Panama in 1575, climbing the coastal cordillera to get to the Pacific Ocean, then referred to by the Spanish as the Mar del Sur.
Departing from Acla (in modern Darién Province), he descended to the Chucunaque River, which Vasco Núñez de Balboa had also used in 1513 to cross the isthmus, first following the coast to the town of Careta, then receiving assistance from the Cimarrones for the crossing itself.
In May 1572, John Oxenham joined Francis Drake's expedition to Central America, along with Drake's brothers John and Joseph (who both died on the voyage). They left Plymouth with a total of 73 men in the Pasha (70 tons) and Swanet (25 tons), set up an operating base in a creek in the Isthmus of Panama, and raided the Isle of Pines, Cartagena, and Nombre de Dios to divert the attention of the Spanish. With the help of the Cimarrones, they set an ambush on the route for transporting silver across Panama and captured a mule train that was passing during the night. The small guard fled, and Drake sailed back to Plymouth in August 1573 with a significant treasure.
After participating in Drake's successful voyage, Oxenham launched his own expedition to Panama, leaving Plymouth on 9 April 1576 with an 11-gun frigate (100–140 tons, name unknown) and 57 men, and after taking some prizes and prisoners, hid his ship and prizes and proceeded on the Panama mainland. The Cimarrones guided Oxenham and his men across the Cordillera de San Blas to the head of the Chucunaque River, which flows into the Pacific Ocean. During the winter, Oxenham's men and their Cimarron allies felled and milled cedar trees to build a shallow-draft 45 foot, oared boat, that they then floated down the river and into the ocean, making Oxenham the first Englishman to build a vessel in the New World, and the first to sail in the Pacific.
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