The warforged are a relatively new race being created by House Cannith during the Last War in 965 YK for the purposes of warfare. The Warforged are sentient constructs and have free will, which earned them the same rights as human citizens in each of their homelands in 996 YK under the Treaty of Thronehold.

Rule page on Eberron Pathfinder site.

The Treaty of Thronehold declared warforged to be free creatures just two years ago, and the living constructs have had little time to create a society or culture beyond the limited soldier culture they possessed during the Last War. What society exists among warforged is largely a remnant of the command structures of the armies of the Last War.

Squads of warforged remain together, bound to one another by their sense of camaraderie. These small groups tackle the challenges of life after war as a unit, often taking similar jobs and living together. Sometimes a squad commander leads these warforged, serving to help the squad find its place in the new world they all live in.

Even those without comrades upon whom they can associate are rarely alone for long, though. Due to their common abilities, warforged without squads often find themselves in similar lines of work. Warforged who work together often elect a leader (independent of the desires of their employer) and become an impromptu squad.

Warforged who are truly alone often seek camaraderie with other groups of creatures. They might be able to find solace among those of other races with whom they work, but many warforged find that other laborers are jealous of their tirelessness and distrustful of their warlike natures.

The strongest bonds formed by warforged are typically with those who judge them by their actions and abilities rather than their past, so it shouldn’t be surprising that many warforged take to a life of adventure or a mercenary existence. In battle against a common foe, the prejudice that warforged typically face fades away, and allies rely on them as they would any friend. Yet even among adventurers, some think of warforged as tools rather than thinking and living creatures; warforged who manage to find true acceptance and respect among other creatures remain steadfastly loyal to them.

Warforged share a common culture mainly because of their outlook. They all seek a place in the world after the Last War. They are all natural warriors, with little that they fear. Extremes of emotion are uncommon, and they are industrious workers. Yet from this common ground, warforged diverge to a myriad of behaviors leaving little that can be called culture or society.

Many warforged adopt the culture of the area they live in. A warforged might even dress in the clothes common to folk in the area and emulate the speech patterns and customs of his neighbors. Some warforged take such efforts to great extremes, exploring their living nature by engaging in eating, and “sleeping” by remaining inactive during the night.

Other warforged deny their living nature and instead revel in their differences from humanoids. These warforged never wear clothes or partake in the celebrations or rituals of the societies in which they live. They remain active constantly, taking pride in their tireless strength. Such warforged often take up professions where their construct nature gives them a great advantage, such as mining and underwater salvaging.