Latgalians

Latgalians, sometimes also Ancient Latvians (Latin: Lethi, Letthigalli, Low German: Letti, Lethi, modern Latvian: latgaļi, letgaļi, leti, variant translations also include Latgallians, Lettigalls or Lettigallians) were an ancient Baltic tribe.

They likely spoke the Latvian language, which probably became the lingua franca in present-day Latvia during the Northern Crusades due to their alliance with the crusaders. Latgalians later assimilated the neighboring tribes, forming the core of modern Latvians.

The Latgalians were an Eastern Baltic tribe whose origin is little known. In the 5th and 6th centuries they lived in the eastern part of present-day Vidzeme (westwards from the Aiviekste River), and later on in nearly all the territory of that region. In written sources they are mentioned from the 11th century. In the first two decades of the 13th century the (Western) Latgalians allied with German (mainly Saxon) crusaders. Their lands (Eldership of Tālava, Principality of Jersika, Principality of Koknese) as vassal states were incorporated into Livonia.

In the 11th century Eastern orthodoxy started to spread in Latgalian lands from Polotsk and Pskov. In 12th century Latgalian lands and their rulers paid tribute to dukes of Polotsk. In 13th century during the Livonian crusade Latgalian elders changed their Eastern orthodoxy for Roman Catholicism and became vassals of Livonian Order.

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