Dwarves of the Grey Mountains
The Dwarves of the Grey Mountains were the Dwarves of Durin's folk who lived in the Grey Mountains in northern Middle-earth. They fled to the Grey Mountains in Third Age 1981 after a Balrog was unearthed in their ancestral home of Khazad-dûm. Another portion of their clan established the kingdom of Lonely Mountain, but King Thorin I, learning that most of his people remained in the Grey Mountains, abandoned Lonely Mountain to join the Dwarves to the north.
Increasing attacks by Dragons plagued the Dwarves until King Dáin I was slain by a Cold-drake in 2589. Durin's folk then left the Grey Mountains, with some returning to Lonely Mountain while others founded their own kingdom in the Iron Hills.
According to some hints in The Hobbit, and Appendix A of Return of the King, their still was a remnant of the Dwarves in the Grey Mountains during the late Third Age. So it is possible that the Dwarves may have reclaimed their ancient mansions from the Dragons and Orcs who still dwelt their, and started a new kingdom, or some colonies.