Complex sentence: It was clear that there could be no new attack on the Frisians under these circumstances, so apart from some confiscations of Frisian property in Holland, and a renewal of the hostilities at sea, the Frisian issue disappeared into the background.
Split into simpler sentences: It was clear that there could be no new attack on the Frisians under these circumstances. So apart from confiscations of Frisian property in Holland, and a renewal of the hostilities at sea, the Frisian issue disappeared into the background.