It stretched down to the former County of Groitzsch in the south, and up to Sangerhausen in the west, including the town of Weißenfels which became the margravial residence.

Upon the death of Margrave Conrad in 1156, the Wettin domains of Meissen and Lusatia were re-arranged.

However, an Imperial State in its own right was not established until in 1261, when Margrave Henry the Illustrious (against legal provisions) split off the western Landsberg territory from the March of Lusatia as a separate margraviate for his second son Theodoric.

In 1327 the Welf duke Magnus I of Brunswick-Lüneburg inherited Landsberg by marrying Sophia of Brandenburg-Stendal, the sister of the last Ascanian margrave Henry II and also the niece of the German king Louis IV, who had seized the Brandenburg possessions in 1320.

Duke Magnus sold Landsberg to Margrave Frederick II of Meissen in 1347, and in this way the former margraviate finally fell back to the House of Wettin.