The name Sumorsǣte is Old English and may be a shortened form of Sumortūnsǣte, meaning "the people living at or dependent upon Sumortūn", i.e. the modern town of Somerton.
[1] The origin of Somerton itself is unknown; it may mean 'The sea-lake enclosure' from the Old English sae, mere and tun[2] or possibly "summer farmstead", from sumer and -tūn.
[4] When King Alfred coined the future county motto 'Sumorsǣte ealle' in the ninth century, he referred to the people of Somerset as the Sumortūnsǣte.
[12] The Saxons conquered Bath following the Battle of Deorham in 577, and the border was probably established along the line of the Wansdyke to the north of the Mendip Hills.
Then Cenwalh of Wessex broke through at Bradford-on-Avon in 652, and the Battle of Peonnum possibly at Penselwood in 658, advancing west through the Polden Hills to the River Parrett.