Nestor the Chronicler in the context of "Masovians"

Eastern Lutheranism (also known as Byzantine Lutheranism or Byzantine Rite Lutheranism) refers to Eastern Protestant Lutheran churches, such as those of Ukraine and Slovenia, that use a form of the Byzantine Rite as their liturgy. It is unique in that it is based on the Eastern Christian rite used by the Eastern Orthodox Church, while incorporating theology from the Divine Service contained in the Formula Missae, the base texts for Lutheran liturgics in the West.

Eastern Lutherans use the Julian calendar for the calendar and thus observe feast days and liturgical seasons, such as Great Lent, in a fashion similar to Orthodox customs. As such, many Byzantine Lutheran holy days are shared with those of the Eastern Orthodox Church; in addition, Eastern Lutheran churches are constructed in accordance with Byzantine architecture. Posture during worship, such as bowing, is identical to that in other parts of Eastern Christianity. Within Byzantine Rite Lutheranism, the calendar of saints includes persons esteemed in Eastern Christianity, such as John Chrysostom and Nestor the Chronicler, as well as those specific to the Lutheran Church, such as Lucas Cranach the Elder and Martin Luther.

The Primary Chronicle, shortened from the common Russian Primary Chronicle (Church Slavonic: Повѣсть времѧньныхъ лѣтъ, romanized: Pověstĭ vremęnĭnyxŭ lětŭ, commonly transcribed Povest' vremennykh let (PVL), lit. 'Tale of Bygone Years'), is a chronicle of Kievan Rus' from about 850 to 1110. It is believed to have been originally compiled in the Kiev area in the 1110s. Tradition ascribed its compilation to the monk Nestor (Nestor's Chronicle) beginning in the 12th century, but this is no longer believed to have been the case.

The title of the work, Povest' vremennykh let ("Tale of Bygone Years") comes from the opening sentence of the Laurentian text: "These are the narratives of bygone years regarding the origin of the land of Rus', the first princes of Kiev, and from what source the land of Rus' had its beginning". The work is considered a fundamental source for the earliest history of the East Slavs.

"Polish tribes" is a term used sometimes to describe the tribes of West Slavic Lechites that lived from around the mid-6th century in the territories that became Polish with the creation of the Polish state by the Piast dynasty. The territory on which they lived became a part of the first Polish state created by duke Mieszko I and expanded at the end of the 10th century, enlarged further by conquests of king Bolesław I at the beginning of the 11th century.

In about 850 AD a list of peoples was written down by the Bavarian Geographer. Absent on the list are Lechitic-speaking Polans, Pomeranians and Masovians, who became known later and were written about by Nestor the Chronicler in his Primary Chronicle (11th/12th century).