Governorate of Terra Australis

The Governorate of Terra Australis or Governorate of Pedro Sancho de la Hoz was a Spanish Governorate of the Crown of Castile created in 1539 which was granted to Pedro Sánchez de la Hoz and consisted, according to the Spanish Royal Decrees, in all the territories to the south of the Strait of Magellan until the South Pole, and, to the east and west, the borders were the ones specified in the treaties of Tordesillas and Zaragoza, respectively, claiming also the unexplored parts which were theorized as part of the Terra Australis hypothetical continent. The Spanish legal domain was transferred to the Governorate of Chile by ordering the governors to explore and conquer the lands to the south of the strait.

Source: Wikipedia — Governorate of Terra Australis (CC BY-SA 4.0)