The southeast of the Capetian royal Domain remained for a long time unknown by studies on the beginnings of Romasnesque architecture. This is largely connected to the marginal position which it occupies compared with the large sets of the historiography, an established fact which ensues as we had the opportunity to show it of a long historic evolution since the Celtic period when the zone was subdivided between Sénons and Carnutes. The first Capetian sovereigns however carried a particular interest in this region, trying in the 11th century to unify the space between their three big centers : Orléans, Étampes and Melun, in front of pushes of their bléso-champenois rivals. The architectural activity then seems to be in full swing, with very numerous constructions, certainly secondary, but testifying of a certain architectural dynamism at that time. The examination of the most important buildings, confronted with the other key realizations led by the Capetians in the rest of their royal Domain, allows us to envisage the development of a artistic policy, favoring certain architectural monumental forms as tower-hall and harmonious bedhead, in a clear will on behalf of the new sovereigns to stand out visually in the landscape, to position in heirs of their Carolingian predecessors and to stand out in front of their ottonian contemporaries, by taking back their most symbolic architectural forms. These results can’t hide on the other hand questions left unsettled, in particular as regards the datings of buildings considered here. The architecture indeed seems rather uniform, between walls with small rubbles, opus spicatum, re-uses of high-medieval sarcophagus, and beginnings of carved stone ; and the generally admitted criteria of dating oppose those of the rare preserved decorations.