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Stadeck was an important family of ministeriales in Styria during the 13th and 14th centuries.
The family is named for Stattegg castle, beginning with Rudolph I (1192–1230). His son Rudolph II (d. 1261) was a leading minnesinger, featured in Codex Manesse.
The male line of the family died out with Johann of Stadeck in 1399.
References
Karl Weinhold, 'Der Minnesinger von Stadeck und sein Geschlecht', Sitzungsberichte der philosophisch-historischen Classe der kaiserlichen Akademie der Wissenschaften vol. 35, Vienna, 1860.
Joseph Bergmann, Die letzten Herren von Stadeck und ihre Erben, Sitzungsberichte... vol. 9, Vienna, 1853.