Angbor was a man of Gondor, of Dunadan descent. He was the Lord of Lamedon during the War of the Ring. The forces of Lamedon fought with the ships of the Corsairs that were sailing up the river Gilrain, going to aid the armies of Mordor and Harad at the seige of Minas Tirith.
When Aragorn came from the Paths of the Dead, it was the men of Lamedon, led by Angbor, who aided him with the ships of the Corsairs.
Angbor assisted Aragorn II with all the horsemen he could muster, and his forces fought at Minas Tirith.
When Aragorn told of what happened on the Paths of the Dead, and the taking of the Ships of the Corsairs, he named Angbor, Angbor the Fearless, for his conduct in the face of the Dead that were led by Aragorn, the heir of Isildur.
Angbor seemed to be a fair lord, and was famed afterwords for his fearlessness.