Fëanorians

When Fëanor and his people crossed into Middle-earth, they burned the ships they had used, abandoning the rest of the Noldor on the frozen shores of Aman. Fëanor's half-brother Fingolfin led these abandoned Elves across the Grinding Ice of the Helcaraxë, but a rift had been created between the two branches of that people.

After Fëanor's death, his eldest son Maedhros attempted to heal the rift by refusing the High Kingship of the Noldor, allowing it to pass instead to Fingolfin. The seven Sons of Fëanor then departed into the east of Beleriand, where they guarded the March of Maedhros and the lands to the south of it.

Thus the Sons of Fëanor dwelt apart from the followers of Fingolfin, whose lands were mainly in the northern and western regions of Beleriand. Though acknowledging Fingolfin's Kingship in principle, in practice the Fëanorians looked to Maedhros as their leader. At times relations were friendly, and during the Union of Maedhros the two branches of the Noldor truly allied against Morgoth for a brief time. In the end, the workings of the Oath of Fëanor divided the Noldor once again; before the end of the First Age five of the seven Sons of Fëanor had been slain in battle against their own people.