The Lithuanian nobility or szlachta of the Grand Duchy of Lithuania (Lithuanian: bajorija, šlėkta, Polish: szlachta Wielkiego Księstwa Litewskiego) was historically a legally privileged hereditary elite class in the Grand Duchy of Lithuania and Polish Lithuanian Commonwealth (including during period of foreign rule 1795–1918) consisting of Lithuanians from Lithuania Proper; Samogitians from Duchy of Samogitia; following Lithuania's eastward expansion into what is now Belarus, Ukraine and Russia, many ethnically Ruthenian noble families (boyars); and, later on, predominantly Baltic German families from the Duchy of Livonia and Inflanty Voivodeship.[1]
Initially, the privileged social group of the Grand Duchy of Lithuania was called boyars. Boyars became part of the szlachta (nobility) during the Union of Horodło on October 2, 1413, initiating nobility in the Grand Duchy of Lithuania following the Western European model (with a hereditary system of heraldic identification), as well as an increase in the position of the Greater Lithuanian nobility. The Grand Duchy of Lithuania adopted Polish institutions of castellans and voivodes, and 47 selected boyars of Grand Duchy of Lithuania of the Catholic faith were adopted by Polish noble families and received Polish coats of arms.[2]
With the Union of Lublin, nobility of the Grand Duchy of Lithuania and the nobility of the Kingdom of Poland became a common entity of the Polish–Lithuanian Commonwealth, which had one of the largest percentages of nobility in Europe, with szlachta constituting close to 10% of the population, but in some constituent regions, like Duchy of Samogitia, it was closer to 12%. However, the high nobility was extremely limited in number, consisting of the magnates and later, within the Russian Empire, of princes.
Families of the nobility were responsible for military mobilization and enjoyed Golden Liberty; some were rewarded with additional privileges for success on the battlefield. In the Grand Duchy of Lithuania, ducal titles were mostly inherited by descendants of old dynasties while the relatively few hereditary noble titles in the Kingdom of Poland were bestowed by foreign monarchs. The Polish–Lithuanian Commonwealth had one of the largest percentages of nobility in Europe, with szlachta (nobility) constituting close to 10% of the population, but in some constituent regions, like Duchy of Samogitia, it was closer to 12%. However, the high nobility was extremely limited in number, consisting of the magnates and later, within the Russian Empire, of princes.
Over time, the vast majority of the nobility of the Grand Duchy of Lithuania voluntarily became Polonized and recognized Polish national thought as a natural continuation of Greater Lithuanian national thought[3].