Why did the settlers of Jamestown surround their settlement with large wooden walls?

Surrounding Jamestown Fort was a triangular wooden palisade (a fence or wall made ... (Wattle and daub is a building material used for making walls, in which a ... at Jamestown Settlement may have served as the colonial governor's house. ... to move inland away from the fertile river valleys that had long been their home.

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.