Sir Humphrey Gilbert was an English adventurer, explorer, member of parliament and soldier who served during the reign of Queen Elizabeth I and was a pioneer of the English colonial empire in North America and the Plantations of Ireland. He was a maternal half-brother of Sir Walter Raleigh and a cousin of Sir Richard Grenville.

The English overseas possessions, also known as the English colonial empire, comprised a variety of overseas territories that were colonised, conquered, or otherwise acquired by the former Kingdom of England during the centuries before the Acts of Union of 1707 between the Kingdom of England and the Kingdom of Scotland created the Kingdom of Great Britain. The many English possessions then became the foundation of the British Empire and its fast-growing naval and mercantile power, which until then had yet to overtake those of the Dutch Republic, the Kingdom of Portugal, and the Crown of Castile.