three-aisled longhouse started to be built in the south of Scandinavia. These houses were
significantly wider: up to 12. 5 m in width. They had only two pairs of roof-supporting
posts inside the house, which created more spacious rooms. They seem also in general to
be considerably taller than the older houses. The height to the roof has been calculated as
up to 10 m in the biggest houses. Probably the houses also had an upper floor. This type
of house, called the ‘Trelleborg house’ after the place on Zealand in Denmark where they
were first discovered, had substantial, supporting posts heavy at the sides outside long
convex walls, which gave the house a resemblance to a boat. These houses could be
found, other than in the Danish fortresses from the Viking Age, first and foremost on
the largest farms – the farms of the aristocrats – and could have several functions
(Figure 7. 1 ). The so-called ‘Trelleborg houses’ were in use in southern Scandinavia until
the beginning of the Middle Ages – the twelfth and the beginning of the thirteenth
century. But at that time several of them no longer contained inner roof-bearing posts;
instead the houses had developed into one-aisled constructions. Separate smaller one-
aisled houses existed even during the Viking Age in the south Scandinavian area, but it
was not until later during the thirteenth century that three-aisled houses were com-
pletely replaced by one-aisled houses in south and west Scandinavia (Hvass 1988 ; Skov
1994 ; Christensen 1999 ; Rasmussen 1999 ; Carelli 2001 : 48 ff.; Jørgensen 2001 , 2002 ;
Ethelberg 2003 : 345 ff.; Herschend and Kaldal Mikkelsen 2003 : 67 ff.; Söderberg
2005 : 111 ff., 192 ff.).
On the other hand this technological building change entered eastern Scandinavia
much earlier. On the two large islands in the Baltic Sea, Öland and Gotland, the old
three-aisled houses began to be replaced by one-aisled houses with roof-supporting
timber-framed walls already at the end of the Merovingian period (Carlsson 1979 , 1981 ,
2005 ; Thunmark 1979 ; Fallgren 1994 : 120 ; 1998 : 73 ; 2006 : 157 f.), maybe through
influences from Slavic and Baltic architecture. During the Viking Age it seems that only
one-aisled houses existed on these islands. These new rectangular or square houses were
Figure 7. 1 Reconstruction of a ‘Trelleborg house’ from Fyrkat, northern Jutland, Denmark
(from Birkebæk & Bau 1982 ).–– Jan-Henrik Fallgren––