Jutes were one of the Germanic people who invaded England along with the Angles and Saxons, and who later became part of the people referred to as Anglo-Saxons.
Hengist and Horsa, chieftains of the Jutes, were the first to arrive with three longships of fighting men, not initially as an invasion but by invitation. They had been invited here by Vortigern, a Welsh king who had come to rule large parts of southern England. The reason for their invitation was to counter repeated raiding by the Pictish people of Scotland. The Jutes defeated a Pictish army sent against them, but according to the Venerable Bede in his eighth-century History of the English People, they also noted that the other defenders were a cowardly lot. Hengist and Horsa sent messages back to their friends and relatives, telling them of the land and loot that was there for the taking, resulting in later invasions (Jutes, Angles and Saxons) around 450 AD.
Information taken from various sources on the WWW