While most of the other nations of Khorvaire have their own unique traditions of nobility, a few have inherited some elements from Galifar, and these are briefly addressed below. A critical point to consider with any of the other nations is that the Position of Privilege benefit reflects a broad recognition of your authority. If you wield great power within a Lhazaar principality but don’t have any influence beyond it, you don’t need to take the noble background; you can be a sailor or a pirate, and work out the other elements of your backstory with your DM. Your background benefit reflects the aspect of your background that will regularly come into play. If you want to have an interesting story hook that may well never actually come up in the campaign, that comes down to the approval of your DM.
From the chaos and devastation of the Last War, new nations came into being as the Five Nations lost their hold on lands that were once part of the united Galifar. The Eldeen Reaches splintered off from Aundair as the war raged, causing bad blood between the nations that remains to this day. The Shadow Marches, Droaam, and Zilargo are no longer part of Breland as they once were, and the parts of Cyre that survived the Mourning are now the sovereign nations of Darguun, Valenar, and parts of the Talenta Plains. Karrnath lost territory that now forms Q’barra, the rest of the Talenta Plains, the Mror Holds, and the Lhazaar Principalities.
In all, the Treaty of Thronehold recognized twelve sovereign nations: Aundair, Breland, Darguun, the Eldeen Reaches, Karrnath, the Lhazaar Principalities, the Mror Holds, Q’barra, the Talenta Plains, Thrane, Valenar, and Zilargo. Three other regions—the Demon Wastes, Droaam, and the Shadow Marches—are wild lands ruled by fiends and monsters, not nations recognized by any formal treaty, but regions whose borders are crossed only by the most daring adventurers.
Source: Eberron Campaign Guide