Saxon Eastern March
It was his task to collect tributes and to overcome revolts or rebellions in the frontier areas, later partly superseded by Otto's Saxon deputy Hermann Billung.In 963, Gero in late age waged another military campaign against the Slavic Lusatian (Lusici) tribes, up to the border with the Polish lands ruled by Mieszko I.While the Margraviate of Landsberg and the County of Brehna split off from the march, further parts in the west were claimed by the Ascanian Dukes of Saxe-Wittenberg and the Counts of Anhalt.The term Osterland (terra orientalis) is still used today to describe the historic region east of the Saale in the present-day states of Thuringia, Saxony and Saxony-Anhalt, which was once at the centre of the march.While the borders of the Ostmark changed frequently, in modern times, the term is generally understood to mean the area between the Saale and Mulde rivers.