This study is based on ten examples. The castles examined often lack clear criteria for a substantiated assessment (incomplete written evidence, missing excavations). The following contexts are analyzed: a) two equal-ranking castles existing at the same time; b) castle displacements: two equal-ranking castles that supersede one another; c) construction of a second castle after a transition of power; d) two equal-ranking, contemporaneous castles belonging to rival dominions; e) hierarchical relationship of two castles. The more important functional differentiation is only between possibilities a), d) and e). There are also other constellations that this article does not cover.