During the Viking Age, Birka was an important trading center. 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 Scandinavia and their influence on the subsequent history of Europe. 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 and Novgorod 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 (archbishop of Bremen-Hamburg, c. 865) describes the missionary work of Ansgar around 830 at Birka, and Gesta Hammaburgensis Ecclesiae Pontificum (Deeds of Bishops of the Hamburg Church) by Adam of Bremen in 1075 describes the archbishop Unni, who died at Birka in 936. St Ansgar's work was the first attempt to convert the inhabitants from the Norse religion to Christianity, and it was unsuccessful.
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.
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, the near-by settlement of 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. The Baltic island of Gotland was also in a better strategic position for Russian-Byzantine trade, and was gaining eminence as a mercantile stronghold. Historian Neil Kent has speculated that the area may have been the victim of an enemy assault.
In search of Birka, National Antiquarian Johan Hadorph was the first to attempt excavations on Björkö in the late 17th century. The later excavations soon indicated that a major settlement had been located on the island and eventually. 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.References:
The Broch of Gurness is an Iron Age broch village. Settlement here began sometime between 500 and 200 BC. At the centre of the settlement is a stone tower or broch, which once probably reached a height of around 10 metres. Its interior is divided into sections by upright slabs. The tower features two skins of drystone walls, with stone-floored galleries in between. These are accessed by steps. Stone ledges suggest that there was once an upper storey with a timber floor. The roof would have been thatched, surrounded by a wall walk linked by stairs to the ground floor. The broch features two hearths and a subterranean stone cistern with steps leading down into it. It is thought to have some religious significance, relating to an Iron Age cult of the underground.
The remains of the central tower are up to 3.6 metres high, and the stone walls are up to 4.1 metres thick. The tower was likely inhabited by the principal family or clan of the area but also served as a last resort for the village in case of an attack.
The broch continued to be inhabited while it began to collapse and the original structures were altered. The cistern was filled in and the interior was repartitioned. The ruin visible today reflects this secondary phase of the broch's use.
The site is surrounded by three ditches cut out of the rock with stone ramparts, encircling an area of around 45 metres diameter. The remains of numerous small stone dwellings with small yards and sheds can be found between the inner ditch and the tower. These were built after the tower, but were a part of the settlement's initial conception. A 'main street' connects the outer entrance to the broch. The settlement is the best-preserved of all broch villages.
Pieces of a Roman amphora dating to before 60 AD were found here, lending weight to the record that a 'King of Orkney' submitted to Emperor Claudius at Colchester in 43 AD.
At some point after 100 AD the broch was abandoned and the ditches filled in. It is thought that settlement at the broch continued into the 5th century AD, the period known as Pictish times. By that time the broch was not used anymore and some of its stones were reused to build smaller dwellings on top of the earlier buildings. Until about the 8th century, the site was just a single farmstead.
In the 9th century, a Norse woman was buried at the site in a stone-lined grave with two bronze brooches and a sickle and knife made from iron. Other finds suggest that Norse men were buried here too.