She was the renowned explorer who successfully became the second person alive who circumnavigated the globe, paving the way for England to become the dominant superpower of the Age of Discovery with its earnings. She also played a significant role in the defeat of the Spanish Invincible Armada and brought Spain - which was called "the Kingdom on which the sun never sets" - to the edge of collapse. In Fate/Extra

Spoiler

She is a Rider class servant under the control Shinji Matou.

(Source: Type-Moon Wikia)