In 1035 the Salian emperorConrad II marched against the rebellious Duke Adalbero of Carinthia. In his attendance was Count Siegfried as his close companion, who thus arrived from Rhenish Franconia in the southeastern estates of the German kingdom. Adalbero was deposed and succeeded by the Salian duke Conrad the Younger in 1036. Siegfried married ? Richgard, the heiress of Count Engelbert IV in the Puster Valley from the Carinthian family of the Sieghardinger and Aribonids. Through the marriage with Richgard, he obtained large possessions in Tyrol and also in Carinthia, for example the Lavant Valley and probably also Laško and some other parts in the March of Carniola like the territories around Ljubljana. In the year 1044 he documents as ruling Count at Sponheim. In 1045 King Henry III of Germany granted Siegfried the territory of the Hungarian March at the eastern frontier of the March of Austria as a fiefdom. However, he kept and managed this land only for a short period. The Hungarian March was finally dissolved and incorporated under the rule of the Babenberg margrave Ernest of Austria from 1055. In 1048 Siegfried documents as a Gaugraf in the Tyrolean Puster Valley and in the Carinthian Lavant Valley; he must therefore have already succeeded to his father-in-law Count Engelbert IV as heir to this territory by then. He overtook likewise the possessions of his father-in-law in the Duchy of Bavaria. Besides he soon held the office of a Vogt in the bishoprics of Brixen and Salzburg. Siegfried received likewise possessions in Lower Carinthia and in eastern Upper Bavaria. In 1064 Siegfried joined the pilgrimage of Archbishop Siegfried I of Mainz to Jerusalem. On his way back, one year later, he died on the transit through Bulgaria. There he was also buried, before his widow Richgard released the corpse and let him be buried in the parish church of Sankt Paul im Lavanttal he had planned and constructed. In the year 1909 the Siegfriedstrasse in the Floridsdorf district of Vienna was named after him.
Issue
From Siegfried's marriage with Richgard Countess of Lavant Valley several children were born:
Dotzauer, Winfried: Geschichte des Nahe-Hunsrück-Raumes von den Anfängen bis zur Französischen Revolution. Stuttgart, Franz Steiner Verlag / 2001
Fuchs, Walter: Schloss Ortenburg, Ortenburger Baudenkmäler und die Geschichte der Reichsgrafschaft Ortenburg, Ortenburg / 2000
Hausmann, Friedrich: Die Grafen zu Ortenburg und ihre Vorfahren im Mannesstamm, die Spanheimer in Kärnten, Sachsen und Bayern, sowie deren Nebenlinien, erschienen in: Ostbairische Grenzmarken - Passauer Jahrbuch für Geschichte Kunst und Volkskunde, Nr. 36, Passau / 1994
Hausmann, Friedrich: Siegfried, Markgraf der "Ungarnmark" und die Anfänge der Spanheimer in Kärnten und um Rheinland. In: Jahrbuch für Landeskunde von Niederösterreich, Neue Folge Band 43. Wien 1977, S. 115–168
Gruden, Josip: Zgodovina slovenskega naroda. Celovec, Družba sv. Mohorja/ 1910
Hauptmann, Ljudmil: Nastanek in razvoj Kranjske. Ljubljana, Slovenska matica / 1999
Kos, Milko: Zgodovina Slovencev. Ljubljana, Jugoslovanska knjigarna / 1933
Pellender, Heinz: Tambach - vom Langheimer Klosteramt zur Ortenburg'schen Grafschaft - Historie des Gräflichen Hauses Ortenburg, des Klosteramtes und Schlosses Tambach, 2. Auflage Coburg / 1990
Ortenburg-Tambach, Dr. Eberhard Graf zu: Geschichte des reichsständischen, herzoglichen und gräflichen Gesamthauses Ortenburg - Teil 1: Das herzogliche Haus in Kärnten., Vilshofen / 1932
Vengust, Marko: Kostanjevica na Krki in koroški vojvode Spanheimi. In: Kostanjeviške novice, n. 36. Kostanjevica. p. 23, 2008