They also had a stable coinage and government administration going on by the 11th Century
They also had a form of early democracy too. Which William the Unmentionable promptly did away with in order to implement the foulness that was the Feudal System (aka legalised slavery)
Which makes it more ironic that William claimed that Edward had promised him the kingship - it wasn't up to Edward to give it to him. It was up to the Witan to select the next king..