Chester 616 is now available in MP!

[stockwellpete]

"And here Æðelfrið led his army to Chester, and there slew countless Welsh. And came about Augustinus's prophecy, that he said "If they do not have peace with us, they will die at the hands of the Saxons." There also were slain 200 priests who came there to pray for the Welsh army. Scrocmail was called their leader, and he escaped as one of fifty."
Anglo-Saxon chronicle 606 AD

"The Britains that dwelt about Chester, through their stoutnesse prouoked the aforesaid Edelferd king of the Northumbers vnto warre: wherevpon to tame their loftie stomachs, he assembled an armie & came forward to besiege the citie, then called of the Britains Chester. The citizens coueting rather to suffer all things than a siege, and hauing a trust in their great multitude of people, came foorth to giue batell abroad in the fields, whome he compassing about with ambushes, got within his danger, and easilie discomfited."
from Raphael Holinshed (16thC)

Various dates between 607 and 616 are given for this battle.

Suggested location is Heronbridge to the south of Chester . . .
http://chester.shoutwiki.com/wiki/Heronbridge

After the battle, Chester became an English city.

Bibliography
Battles of the Dark Ages, Peter Marren, 2006.
Britain and the End of the Roman Empire, Ken Dark, 2000.
In Search of the Dark Ages, Michael Wood, 1981.
Viking Britain, Thomas Williams, 2017.
Warfare and Society in the Barbarian West, Guy Halsall, 2003.