Sir Thomas Warner (1580 – 10 March 1649) was a captain in the guards of James I of England who became an explorer in the Caribbean. In 1620 he served at the brief-lived English settlement of Oyapoc in present-day Guyana of South America, which was abandoned the same year. The Dutch controlled most of the territory. Warner is noted for settling on Saint Kitts and establishing it in 1624 as the first English colony in the Caribbean.
Warner was born in Suffolk, England in 1580. He entered the army at an early age, which provided him with his main training.
He later married and started a family with his wife, which included their son Philip. Thomas Warner had an Island Carib mistress on St. Kitts, and their son was called "Indian Warner". Indian Warner was killed in the Dominica Massacre.
Warner became a captain in James I's guards. In 1620 he accepted assignment to the colonies, and took his family with him to the Oyapoc Colony in 1620 in today's Guyana. He served as a captain under the command of Roger North.
Tomas Painton, another captain in the colony, suggested that Warner should try to colonise one of the islands in the Lesser Antilles, which Painton thought had more favourable conditions. In 1623 Warner abandoned his Guiana post and set sail North through the archipelago. Oyapoc was soon abandoned by the English.
After checking each island, Warner decided that Saint Kitts would be the best-suited site for an English colony. He noted its strategic central position ideal for expansion, friendly native population, fertile soil, abundant fresh water, and large salt deposits. He and his family landed on the island and made peace with the local Kalinago people, whose leader was Ouboutou Tegremante. They were part of the indigenous Carib people of the islands.