The Duchy of Samogitia (, , ) was an administrative unit of the Grand Duchy of Lithuania from 1422 (and from 1569, a member country of the Polish–Lithuanian Commonwealth). Between 1422 and 1441 it was known as the Eldership of Samogitia. The Grand Duke of Lithuania also held the title of Duke of Samogitia, although the actual ruler of the province, responsible to the Duke, was known as the General Elder (Seniūnas) of Samogitia. The Duchy was located in the western part of the present Republic of Lithuania. Historically, in the west it had access to the Baltic Sea; in the north, it bordered the Duchy of Courland and Ducal Prussia in the south. During the Middle Ages and until the last partition in 1795, Samogitia had clearly defined borders as the Duchy of Samogitia. Afterwards the area encompassed the Samogitian Diocese. Today Samogitia is one of several ethnographic regions and is not defined administratively. Name Samogitia is a Latinized version of the name Žemaitija, meaning "the Lowlands" as opposed to Aukštaitija for "the Highlands". In the Middle Ages, the names Samaiten, Samaitae, Zamaytae, Samogitia, Samattae, Samethi were used in German and Latin sources. They, together with other variants Schmudien, Schamaiten (German) and Żmudź (Polish), are all derived from the Lithuanian Žemaičiai, dial. Žemaitiai / Žemaitei. Geography The Duchy was located in what today is several counties (apskritis) in Lithuania: a small part of Kaunas County (Kauno Apskritis), the western part Šiauliai County (Šiaulių Apskritis), Tauragė County (Tauragės Apskritis), Telšiai County (Telšių Apskritis), the northern part of Klaipėda County (Klaipėdos Apskritis) and the northern part of Marijampolė County (Marijampolės Apskritis). The major part of Samogitia is located on Western Upland. Lowlands which are referred in its name are on the border between Samogitia and Eastern Lithuania, along the Nevėžis River. The Duchy of Samogitia had the size of approximately 25,700 square kilometers. History Before the formation of the Lithuanian state, Samogitia was ruled by its local noblemen. A chronicle mentions two dukes from Samogitia in 1219 as signatories of the Treaty with Volhynia. Since the formation of the Grand Duchy of Lithuania in the 13th century, Samogitia was its dependent territory, however sometimes the influence of the Lithuanian Grand Duke was very limited. During the rule of the first Lithuanian king, Mindaugas, Samogitians pursued an independent foreign policy and continued fighting with the Knights of the Sword even after King