Complex sentence: The only common institutions of the Livonian estates were the regularly held common assemblies known as "landtag" s. As well as a divided political administration, there were also persistent rivalries between the archbishop of Riga and the "landmeister" of the Order for Hegemony.
Split into simpler sentences: The only common institutions of the Livonian estates were the regularly held common assemblies ("landtag"). The political division was not only in administration, there were also persistent rivalries between the archbishop of Riga and the landmeister of the order for hegemony.