Historians have traced a complicated series of intermarriages by seven Pict royal houses. The end of the Pict royal bloodline came when the crown of Alba and the title "Rex Pictorum", King of the Picts, passed to a Celtic Scot by the name of Kenneth MacAlpin, a son of a Pictish princess. Kenneth MacAlpin harbored familial hatred of the Picts arising from his father's kingship over the Scots being lost to the Pictish king Oengus, who had ruled as both King of Picts and Scots. In an act known as "MacAlpin's Treason", Kenneth murdered the members of the remaining seven royal houses thus securing the Alba throne for the Scots, and the eventual erasure from history of the Pictish race, culture and history. The Picts were fiercely anti-Roman, and a constant thorn in the side of occupying Rome. Although Rome engaged the Picts in constant battles, Rome never succeeded in subjugating either them or their land. The famous Hadrian's Wall, built by Emperor Hadrian was itself an ultimately futile attempt to keep the Picts from their frequent forays against the Romans in the south of Britain. The wall stretched 70 miles from east to west coasts, and extensions made to it by subsequent Roman leaders were all to no avail The Romans referred to them in Latin as "Pictii", which translates as "The Painted Ones". This was in reference to the elaborate tribal tattoos with which the Picts decorated their entire bodies. There is little known of the Picts today, which adds weight to the words of the Pictish chief, Calgacus, recorded by Roman writer, Eumenius; "We, the most distant dwellers upon the earth, the last of the free, have been shielded...by our remoteness and by the obscurity which has shrouded our name...Beyond us lies no nation, nothing but waves and rocks"