The collections of the Department of the Archaeology of Balts include artifacts from the times since the fifth century BC to the Middle Ages and the modern era (17th century) coming from the area between the lower Vistula river and the lower Daugava river. The oldest part of the collection of the Balts artifacts in the PMA is a part of the collection of Tyszkiewicz family from Łohojsk (Lahoysk) (western Belarus) as well as the collections from the early medieval cemetery in Marienhaus (now Vilaka in Latvia), from the collection of Zygmunt Gloger.
The first half of the twentieth century brought a series of discoveries, resulting in acquiring by the PMA the artifacts from the sites in Prudziszki (Suwalki Region) Wysokie (Lithuania Zaniemeńska), Sudota, Mieżany (Mezionys) and Żwirble (Zvirblai) (Vilnius Region). Especially the artifacts from the latter site deserve attention due to the richness and unique forms of funeral rites.
After World War II the research within the Comprehensive Yatving Expedition focused on Yatving territory of Suwalki Region. In the collections of the Department, there are, inter alia, artifacts from Szwajcaria (Switzerland) near Suwalki, and Netta. As a result of excavations in the early medieval fortified settelement in Jegliniec a collection was acquired, inter alia, of unique bronze ornaments. As a part of Sudowska Expedition the excavations were conducted at the sites in Rostek - Konikowo, Czerwony Dwór and Niedrzwica near Augustow.