sentences:  The oldest map on which Gries appears (compiled in 1564 by the geometer Tilemann Stella), for instance, is to be found at the Swedish Imperial Archive in Stockholm.Over the centuries, the power structure would change often, with only Gries's local lords, the Counts (later Imperial Counts) of Leyen remaining the same, each holding the fief under his respective overlord.Until the French Revolution, the local ruling structure thus did not change again.