The title was given to the ruler of Nogrod, the southerly of the two great Dwarf-cities that stood in the Blue Mountains during the First Age. Though there were presumably many Lords through the history of that Age, only one appears in records, and even that Lord is not named.
In the First Age 502, this Lord received some of his own people who claimed they had been attacked in Menegroth by King Thingol. The King had requested that they set the Silmaril recovered by Beren and Lúthien into the Nauglamir, the famous Necklace of the Dwarves. According to these survivors, the King had slain the Dwarves rather than render payment for their work (this was a lie: the Dwarves had, in fact, seized the Nauglamir and murdered Thingol).
Thus deceived, the Lord of Nogrod set out in search of revenge. He found Doriath all but defenceless: with the loss of its King, the Girdle of Melian had failed, and Thingol's lords and warriors were leaderless. The Dwarves marched into Menegroth and sacked the Thousand Caves of Doriath, though not without great loss. They emptied its treasuries, and the Lord of Nogrod took the Nauglamir with its Silmaril for himself.
Marching eastward across Beleriand, the victorious Dwarves had almost reached their home when they were in turn assailed, by Beren and his son Dior, aided by the Green-elves of Ossiriand. The Lord of Nogrod saw the remnant of his army defeated in that battle, and he himself fell at Beren's hand.