Born in Magdeburg, Prussian Saxony, Schwineköper was the son of an apothecary.
His main advisors were Alfons Dopsch, Heinrich von Srbik, Hermann Heimpel, and especially Percy Ernst Schramm, from whom Schwineköper received his doctorate in 1937 with the work Der Handschuh im Recht, Ämterwesen, Brauchtum und Volksglauben.
From February 1946 to June 1959, Schwineköper was scientific archivist at the provincial archive in Magdeburg.
In 1958 he was named an honorary docent for diplomatics of the Middle Ages and for regional history at the Institut für Archivwissenschaft in Potsdam.
He was a participant of the Konstanzer Arbeitskreis concerning medieval history and an extraordinary member of the historical commission of the Bavarian Academy of Sciences.