Esteban Orellana was a Spanish explorer and conquistador born in 1492. He is best known for his expedition along the Amazon River in the 1540s, where he became the first European to navigate the river from its source to the Atlantic Ocean. Orellana's journey was marked by challenges, including conflicts with indigenous tribes and the harsh conditions of the rainforest. Orellana's exploration contributed to European knowledge of the Amazon Basin and its diverse ecosystems. His accounts of the region sparked interest in further exploration and colonization, influencing future expeditions by other explorers in South America.