§ Of the Coming of Men into the West The Silmarillion

But some still answered: 'He hates us, rather, and ever the more the longer we dwell here, meddling in his quarrel with the Kings of the Eldar, to no gain of ours.' Many therefore of those that yet remained in Estolad made ready to depart; and Bereg led a thousand of the people of Bëor away southwards, and they passed out of the songs of those days. But Amlach repented, saying: 'I have now a quarrel of my own with this Master of Lies, which will last to my life's end'; and he went away north and entered the service of Maedhros. But those of his people who were of like mind with Bereg chose a new leader, and they went back over the mountains into Eriador, and are forgotten.