 "Expugnatio Hibernica" records that he and Lorcán Ua Tuathail, Archbishop of Dublin sent for Gofraid and others in the Isles, asking them to blockade Dublin by sea.According to the aforesaid source, "the threat of English domination, inspired by the successes of the English, made the men of the Isles act all the more quickly, and with the wind in the north-west they immediately sailed about thirty ships full of warriors into the harbour of the Liffey".Unfortunately for the Irish, Islesmen, and Dubliners, the blockade was ultimately a failure, and Dublin remained firmly in the hands of the English.