In 549, the Plague of Justinian - an outbreak of a strain of bubonic plague - arrived in Britain, and Welsh communities were devastated, with villages and countryside alike depopulated. However, the English were less affected by this plague as they had far fewer trading contacts with the continent at this time. Faced with shrinking manpower and increasing Anglian encroachment, King Brochwel Ysgithrog may have moved the court from Caer Guricon to Pengwern, the exact site of which is unknown but may have been at Shrewsbury, traditionally associated with Pengwern, or the more defensible Din Gwrygon, the hill fort on The Wrekin.