c. 870, CE, April, 23
The Viking invasion of England under the leadership of Ivar the Boneless and his ally Olaf the White on c. April 23, 870, results in the capture of Dumbarton after a four- month siege and the defenders ran out of water. Following the surrender, the Vikings plundered the fortress and reportedly used a fleet of 200 ships to transport prisoners and treasure back to Dublin.