1638Centuries: 16th century - 17th century - 18th century
- March 29 - Swedish colonists establish first settlement in Delaware, called New Sweden.
- Pedro Texeira makes the first ascent of the Amazon River, from its mouth to Quito, Ecuador. The same trip had been made in the opposite direction in 1541.
- The Netherlands colonizes Mauritius.
- Shipwrecked sailors from England found the first known European settlement in Belize.
- Swedish settlers arrive on the ships Kalmare Nyckel and Fågel Grip to the American colony New Sweden (Delaware).
- September 5 - Future King Louis XIV of France
- November 25 - Catherine of Braganza, Queen-Consort of King Charles II of England
- Johann Heinrich Alsted, German theologian