Fishguard lies within the historic Welsh cantref of Cemais, part of the ancient province of Dyfed, within the historic Principality of Deheubarth. During the Viking Age, the coasts of Wales were frequently targeted by Norse raiders. By the late 10th century, Norse trading posts and settlements began to appear in Dyfed, and Fishguard is thought to have been established between 950 and 1000 AD.