May 27

Diego Ramírez de Arellano (c.1580–1624) was a Spanish navigator and cosmographer renowned for his role in the García de Nodal expedition (1618–1619). Tasked with mapping the southern Pacific, he helped discover the Diego Ramírez Islands, the southernmost land known at that time. His detailed observations and charts improved European understanding of treacherous maritime routes around Cape Horn. Working for the Spanish Crown, he combined practical seafaring skills with scholarly cosmography to produce accurate maps and navigation tables. His contributions advanced the science of navigation and aided future explorers in the far southern oceans.

Jedediah Smith was born in 1799 in Bainbridge, New York. He became one of the first American explorers to cross the Rocky Mountains to the Pacific Northwest. Smith mapped uncharted territories, opening the West to fur trade and settlement. He kept detailed journals that remain invaluable records of early American exploration. Renowned for his courage and survival skills, he crossed the Great Basin twice. Smith died tragically on May 27, 1831, during a return expedition in present-day California.