(Νικόδωρος/Nikódōros) from Mantinea; he was of noble birth and a successful athlete who was on the one hand compared as a great ‘legislator’ to Solon, and on the other hand connected with the notorious atheist Diagoras  of Melos (Ael. VH. 2,23; Eust. ad Hom. Od. p. 1860,52ff.). We do not know whether he was the originator of a moderately democratic constitution initiated in 425 or 423 BC in Mantinea (Aristot. Pol. 6,2,1318b 21ff.) [1. 101ff.].
1 H.-J. Gehrke, Stasis, 1985.
K.-J. Hölkeskamp, Schiedsrichter, Gesetz…