Sussex is a region in southern England, which was home to the Southern Saxon Kingdom in the 5th century, and was later and Earldom of England.
The Kingdom of Sussex was established in the late 5th century by the Saxon Aelle, after defeating the native Britons. In the 7th century Bishop Wilfred of York spent 5 years converting the populace.
In the late 8th century Sussex fell under the control of Offa of Mercia. In 825 it was finally absorbed into Wessex.