Juan de Fuca

Ioannis Phokas, better known by his Spanish name Juan de Fuca, was a Greek maritime pilot for the Spanish Empire. 
Voyages to the north.
According to de Fuca himself, he went on two voyages after being told to do so by the leader of New Spain, Luis de Velasco. Both voyages were meant to find the supposed Strait of Anián, which was believed to be a Northwest Passage. The first voyage saw 200 soldiers and three small ships under the overall command of a Spanish captain (with de Fuca as pilot and captain) told the crew to find the Strait of Anián and to fortify and protect it in case the English wanted to take it. 
The first expedition failed. Allegedly due to the captain's wrongdoing, the soldiers rose up against him and returned home to California.
In 1592, on his second voyage, de Fuca was far more successful than his previous voyage. He returned to Acapulco and claimed to have found the strait, with a large island at its opening. However, despite the promises of Velasco, de Fuca never got any of the rewards that he was supposed to get for his service.
Legacy.
When the English captain Charles William Barkley discovered the strait de Fuca had written about, he renamed it the "Strait of Juan de Fuca".
His discoveries in the Western Hemisphere led to the Juan de Fuca tectonic plate being named after him.
Juan de Fuca Provincial Park on Vancouver Island's West Coast is named for the strait, as is the hiking trail of the same name.