Its name comes from Mael meaning 'stone' and dun meaning 'hill'. East Saxons settled the are in the fifth century and the are to the south is still known as the Dengie peninsular after the Dean-ingas. It became a significant Saxon port with a hythe or Quayside, artisan quarters. Evidence of imported pottery from this period has been found in archaeological digs. From 958 there was a royal mint issuing coins for the lat Anglo-Saxon and early Norman kings.
With Colchester it was one of the only two towns in Essex, and King Edward the Elder lived here while combatting the Danish sttlers who had overrun North Essex and parts of East Anglia. A Viking raid was beaten off in 924, but in another raid in 991 the defenders were defeated in the Battle of Maldon and the Vikings received tribute but apparently did not attempt to sack the town. It became the subject of the poem The Battle of Maldon.
According to the Domesday Book there were 180 townsmen in 1086. the town still had the mint and supplied a warhorse and warship for the king's service in return for its priveleges of self-government. There were strong urban traditions here with two members elected to the Commons and three guilds which hosted lavish religious plays. After they were suppressed by puritans in 1576. Then until 1630 professional actors were invited to perform plays, which were also stopped by puritans. From 1570 to about 1800 a rival tradition of inviting prominent clergy to visit the town also existed.