Description: During the Viking Age, Birka on the island of Björkö (literally: "Birch Island") in Sweden, was an important trading center which handled goods from Scandinavia as well as Central and Eastern Europe and the Orient. Björkö is located in the Lake Mälaren, 30 kilometers West of Stockholm, in the municipality of Ekerö. The archaeological sites of Birka and Hovgården, on the neighbouring island of Adelsö, make up an archaeological complex which illustrates the elaborate trading networks of Viking Europe and their influence on the subsequent history of Scandinavia. "Generally regarded as Sweden's oldest town", Birka (along with Hovgården) has been a UNESCO World Heritage Site since 1993.
Established in the middle of the 8th Century and thus being one of the earliest urban settlements in Scandinavia, Birka was the Baltic link in the river and portage route through Ladoga (Aldeigja) and Novgorod (Holmsgard) to the Byzantine Empire and the Abbasid Califate. Birka was also important as the site of the first known Christian congregation in Sweden, founded in 831 by Saint Ansgar.
Sources are mainly archeological remains. No texts survive from this area, though the written text Vita Ansgari ("The life of Ansgar") by Rimbert (c. 865 CE) describes the missionary work of Ansgar around 830 CE at Birca, and Gesta Hammaburgensis Ecclesiae Pontificum (Deeds of Bishops of the Hamburg Church) by Adam of Bremen in 1075 CE describes the archbishop Unni, who died at Birca in 936 CE. St Ansgars work was the first attempt to convert the inhabitants from heathen living to Christianity, and it was unsuccessful.
Both Rimbert and Adam were German clergymen writing in Latin. There are no known Norse sources mentioning the name of the settlement, or even the settlement itself, and the original Norse name of Birka is unknown. Birca is the latinicised form given in the sources and Birka its contemporary, unhistorical Swedish form. The Latin name is probably derived from an Old Norse word "birk" which probably meant a market place. Related to this was the Bjärköa law (bjärköarätt) which regulated the life on market places in Denmark, Norway and Sweden. Both terms in different forms are very common in Scandinavian place names still today leading to speculation that all references to Birca especially by Adam of Bremen were not about the same location.
Both publications are silent on Birca's size, layout and appearance. Based on Rimbert's account, Birca was significant because it had a port and it was the place for the regional ting. Adam only mentions the port, but otherwise Birca seems to have been significant to him because it had been the bridgehead of Ansgar's Christian mission and because archbishop Unni had been buried there.
Vita Ansgari and Gesta are not always unambiguous, which has caused some controversy whether Birca and the Björkö settlement were the same location. Many other locations have been suggested through the years. However, Björkö is the only location that can show remains of a town of Birca's significance, which is why the vast majority of scholars still regard Björkö as the location of Birca.
Birka was abandoned during the later half of the 10th century. Based on the coin finds, the city seems to have silenced around 960. Roughly around the same time, a near-by Sigtuna supplanted Birka as the main trading centre in the Mälaren area. The reasons for Birka's decline are disputed. A contributing factor may have been the post-glacial rebound, which lowered the water level of Mälaren changing it from an arm of the sea into a lake and cut Birka off from the nearest (southern) access to the Baltic Sea. According to the 2006 Encyclopaedia Britannica, the Baltic island of Gotland was also in a better strategic position for Russian-Byzantine trade. It should be noted that the Varangian trade stations in Russia suffered a serious decline about the same date.
After having consistently described Birca as an existing city, Scholia 138 of IV 29 describes Birca's sudden demise. Talking about Adalvard the Younger, the bishop of Sigtuna and later that of Skara, Adam or a later copyist has written:
"During his journey he seized the opportunity to make a detour to Birca, which is now reduced to loneliness so that one can hardly find vestiges of the city; therefore impossible to come upon the tomb of the holy Archbishop Unni."
The remark does not make it clear if Adalvard found the city destroyed or if that had happened after his visit and the later remark was just to warn the future pilgrims not to go there anymore in vain. As Adalvard was back in Bremen already by 1069 and is mentioned as one of Adam's sources of information, it would have been expected that word about Birka's destruction had reached also Adam before he published his work half a decade later.
Björkö archaeological site.
The exact location of Birca was also lost during the centuries, leading to speculation from Swedish historians. However, the island of Björkö was first claimed to have been Birka already about 1450 in the so-called "Chronicle of Sweden" (Prosaiska krönikan):
"And there were three capitals in Sweden two of which were not long away from Uppsala (vpsala). The one was called Sigtuna (siktuna) and the other Birka (birka). Birka was on an island in Lake Mälaren (mälar) that is called Björkö (birköö). The third was in Westgötaland (westergötlandh) and was called Skara (skara)."
In search of Birka, National Antiquarian Johan Hadorph was the first to attempt excavations on Björkö in the late 17th century.
In the late 19th century, Hjalmar Stolpe, an entomologist by education, arrived on Björkö to study fossilized insects found in amber on the island. Stolpe found very large amounts of amber on the island, which is unusual since amber is not normally found in lake Mälaren. Stolpe speculated that the island may have been an important trading post, prompting him to conduct a series of archeological excavations between 1871-95. The excavations soon indicated that a major settlement had been located on the island and eventually Stolpe spent two decades excavating the island. After Björkö came to be identified with ancient Birka, it has been assumed that the original name of Birka was simply Bierkø (sometimes spelt Bjärkö), an earlier form of Björkö.
Ownership of Björkö is today mainly in private hands, and used for farming. The settlement site, however is an archaeological site, and a museum has been built nearby for exhibition of finds, models and reconstructions. It is a popular site to visit during the summer times.
The archaeological remains are located in the north part of Björkö and span an area of about 7 hectares (17 acres). The remains are both burial-sites and buildings, and in the south part of this area, there is also a hill fort called "Borgen" ("The Fortress"). The construction technique of the buildings is still unknown, but the main material was wood. An adjacent island holds the remains of Hovgården, an estate which housed the King's retinue during visits.
Approximately 700 people lived at Birka when it was as largest, and about 3,000 graves have been found. Its administrative center was supposedly located outside of the settlement itself, on the nearby island of Adelsö. According to Rimbert, the settlement itself was fortified by a wooden palisade and its harbour was guarded by pilings driven into the bottom of the lake, limiting the number of ships able to pass into it. However, remains of these have not been found on the Björkö site.
The most recent large excavation was undertaken between 1990-95 in a region of "black earth", believed to be the site of the main settlement. Björkö is today mainly agricultural, and shipping lines carry tourists to the island, where a museum showcases a view of life during the Viking era.
(Photos from Oslo University and Netix.cz, text from Wikipedia)