They lived by agriculture and raising cattle. In the late 1st century the Romans referred to the 'Greater Frisii' as living to the east of the lake Flevo, and the 'Lesser Frisii' to the west of it, so-called for their proportional power, and with the settlements of both stretching along the border of the Rhine to the ocean. (The shape of the Netherlands/Low Countries has varied extremely in the last 2000 years. Historic maps should always be used or modern maps should be adapted. Sea level rise and storm surges destroyed 900 000 hectares. 500 000 hectares were reclaimed since the year 1200.)