They Ruined a Country

Sounds intriguing:

The Byzantine-early Islamic transition on the Palestinian coastal plain: 

a re-evaluation of the archaeological evidence

by Itamar Taxel

Abstract
The Muslim conquest of Palestine, which put a final end to the Byzantine hegemony on that part of the eastern Mediterranean, is considered in recent studies to have been a generally non-violent event, in which the negative impact on the continuity of local settlement was for the most part peripheral. While the first assumption may be true [??? "non-violent"], the latter seems too optimistic, especially with regard to the Palestinian Mediterranean coastal plain. A re-evaluation of the archaeological and some historical evidence for the period between ca. 640 and 700, regarding a selection of urban and rural excavated coastal sites and survey maps, shows that the Muslim conquest had various short- and long-term impacts on every settlement, including economic, social and/or functional changes. Generally speaking, the archaeological evidence from the Palestinian coast (and especially the seashore belt) at the beginning of early Islamic times presents a pattern of decline, or abatement. This of course occurred gradually, and the exact process varied from place to place.

My understanding?

They ruined the Land of Israel. 

^