Magdeburg is the capital of the German state Saxony-Anhalt. The city is situated at the Elbe river. Otto I, the first Holy Roman Emperor and founder of the Archdiocese of Magdeburg, was buried in the city's cathedral after his death. Magdeburg's version of German town law, known as Magdeburg rights, spread throughout Central and Eastern Europe. In the Late Middle Ages, Magdeburg was one of the largest and most prosperous German cities and a notable member of the Hanseatic League.