Simplify the following text for a Grade 6 native English-speaking person.
Original: It existed as a kingdom from the 6th century until the English state was made in the 9th century , and as an earldom between 1016 and 1066 .
Simplified: It was to be an earldom after Canute the Great 's conquest of 1016 , from 1020 to 1066 .