The continuity of human establishments in Dărmăneşti depression is emphasized by the pre-existing Dacian settlements in this geographical area, on which the transition period to early feudalism culture was formed. The era of migrations is clearly identified in Dărmăneşti depression by the Cumans, Tatars and Uzi people (which gave the name of the area, Uz), invading these territories.
The Tatar invasion caused the population settled on the confluence of gills Uz and Bărzăuţa to withdraw on the upstream of Uz Valley and on the area of gill Dofteana. After the retreat of Tatars, the population returned to its previous establishments and laid the foundations of Dărmăneşti village, named after their leader, Darman.
This geographical location was the first destination for Transylvanian migrants because of the initial Hungarian persecutions and Austro - Hungarian dominations. And so, the Lapoş village was founded during the Revolution in 1848, on the monastic domains, because of the secularization of wealth monasteries during the reformations of ruler Alexandru Ioan Cuza. In 1864 local residents were given their lands back.
Dărmăneşti village is attested in official documents in 1546, by an act of division of assets left behind by Ivănuş Tatar, between his heirs from Dărmăneşti and Brătuleşti, act reinforced at the Moldavian Chancellery by Prince Petru Rareş.
Dărmăneşti village is certified after the organization of the assigned Trotuş land. The existence of the village was confirmed by the law on administrative-territorial division, in 1864, given by the ruler Alexandru Ioan Cuza. The toponym Dărmăneşti appears registered in old maps from the period of ruler Dimitrie Cantemir, along with other settlements. Friederich von Bawr (1781) determined that Dărmăneşti is settled at the mouth of Uz River, consisting of 11 households, linear placed, on the left side of the river.
The village has seen an evolution in time and space, which in 1989, was among the settlements that gained city status.
Lapoş village was attested in official documents in 1737, when the skete orthodox monastery Lapoş was founded and assigned to Dărmăneşti town in 1774.
Plopu village was officially attested in 1436, when Princes Iliaşi and Ştefan dowered Bâlea Plopescu Plopu village from river Trotuş. Next off, Plopu village was bought in 1518 by Cosma Şarpe, and donated to Tazlău Monastery.
The village of Poiana Uzului was officially attested in 1864 in allotment tables and assigned to Dărmăneşti in 1887.
Sălătruc village was as well attested in official documents in 1864 in allotment tables during the ruler Alexandru Ioan Cuza. Moreover, in a commercial document signed by Alexander the Great are mentioned roads that linked Moldavia with Transylvania by Oituz and Ghimeş Passes, with customs points in Comăneşti, Tîrgu Trotuş and Bacău.
According to Law no. 2/1989 and maintained by Decree-Law no. 38/1990, Dărmăneşti town gained city status. Villages that were assigned to this area were: Dărmăneasca, Joseni, Păgubeni and became neighbourhoods, keeping their initial names. Dărmăneşti city has a component town, Sălătruc, and two villages Lapoş and Plopu.