Early brick use and brick building in mainland Finland

contribution of Koroinen, Early Phases of Turku project and Holy Cross Church of Hattula

Authors

• Tanja Ratilainen Turun yliopisto, arkeologia

DOI: https://doi.org/10.37449/ennenjanyt.99066

Keywords:

Buildings archaeology, church archaeology, medieval archaeology, medieval bricks, medieval roof tiles, optically stimulated luminescence, radiocarbon dating of mortar, raw bricks, scientific dating, town archaeology, tree-ring-wigglematching, unfired bricks

Abstract

This dissertation focuses on the earliest traces of brick use on the mainland of medieval Finland, when and where the brick use and brick building started, the form in which it firstappeared, and how it seems to have developed. In addition, the actors behind the building projects as well as meaning of the brick is shortly discussed. This study goes through threedifferent sites, along with their brick materials and structures: the Koroinen site, where the bishop's see was located in the 13th century; the Early Phases of Turku excavation site aroundTurku Cathedral; and a standing brick building in the Häme region, the Holy Cross Church of Hattula. All of these sites, excavated or studied through archaeology and buildingarchaeology, are unique and are the first in medieval Finland in their own way; Koroinen wasthe first ecclesiastical centre and Turku the oldest town. Holy Cross Church is the only—and thus, the first—parish church built in brick. This material will be discussed in light of new scientific dating and pXRF results and in the context of other sites with brick structures andbuildings, as well as in a larger perspective in the Baltic Sea Region. The dating methods applied are dendrochronology, optically stimulated luminescence, radiocarbon dating and wiggle matching. Materials dated are brick, wood, burnt bone and mortar.

Brick use started on the mainland of medieval Finland in the second half of the 13th century at Koroinen. Bricks were applied in various ways in several different structures,but the first brick buildings were erected only in the second half of the 14th century. Not only roof tiles but also ordinary wall bricks and moulded bricks were imported, but all of them were also locally produced. The bishop was the first to employ brick, likelybecause he wanted to promote Koroinen as an ecclesiastical centre. Right after foundingTurku, brick was applied in the hearths and floors of wooden buildings, which suggeststhat it was also available to other actors in town. On the other hand, bricks, including thespecial raw bricks dealt with in this study, were hardly acquired for just a few modest structures, but it seems likely that a large-scale building project was going on in town inthe early 14th century. In Häme, brick use also probably started in the 14th century. Themain building material of the Häme Castle may have been brick already at the end of the14th century or early 15th century. The Crown seems to have launched brick use in Häme since the Holy Cross Church of Hattula was built only in the second half of the 15th century at the earliest. In the Åland Islands, brick may have been introduced only in the early 14th century. Compared to the Baltic Sea region, brick building was launched modestly in medieval Finland, but as seen in the overview of the known traces and remains, it is richer, more varied and earlier than recently believed.