could, of course, be obtained by plundering. Smaller ships needed smaller investments,
but the figures underline that shipbuilding and seafaring demanded organisation, and
were a heavy burden on society. The leidang – the conscript naval organisation that was
in effect in Scandinavia after and possibly already during parts of the Viking Age –
exemplifies this, but the principle must have also been at work to a lesser extent in trade.
BEFORE THE VIKING AGE
The origin of lap-strake ships
The ships of the Vikings were built shell first on a backbone consisting of keel, stem and
stern. The primary component was a shell of planks, fastened together with clench nails
through their overlapping edges, hence the building technique is called ‘lap-strake’.
Finds of such vessels at the Nydam bog deposit in southern Jutland indicate that this
way of building vessels was replacing sewn plank boats in Scandinavia and northern
Germany in the first centuries ad. At the same time oars replaced paddles as means of
propulsion. It might be that these changes reflect influences from the Roman navy,
which was operating on the Rhine and in the southern North Sea then.
The lap-strake technique produces a hull which is strong and flexible. Caulking
material inlaid between the overlapping planks during the construction made the hull
watertight. Various materials were used, but the most common in Viking ships were
loosely spun yarns of wool. To stiffen the hull, frames were inserted. In the Nydam
vessels they consisted of a naturally curved timber – a compass timber – that was lashed
to cleats carved out of the planks and of a thwart, also lashed. As the thwarts served as
seats for the rowers, they – and thus the frames – sat roughly 1 m apart. This principle
for spacing the framing remained in use until the end of the Viking Age. Rowlocks,
mounted on the gunwale, served the oars, and the vessels could thus not be built higher
than rowing allowed. Boats could be of a notable size; the best preserved of the Nydam
boats, dated to c. ad 320 , had twenty-eight oars and measured c. 23. 5 m in length and
3. 5 m in beam (Bill et al. 1997 : 44 ).
During the fifth to eighth centuries, important improvements took place. Finds from
the Anglo-Saxon ship grave Sutton Hoo in England and from Gredstedbro in south-
western Denmark, show that in the seventh to eighth centuries lashing of frames was
replaced with tree-nailed fastenings in the southern North Sea area. The Storhaug find
from Avaldsnes in Norway shows a large rowing ship with a solid plank with oar holes
instead of rowlocks. The grave, dated to between ad 680 and 750 , is also the first find
in Scandinavia of a ship where the compass timber in the frame does not reach from
gunwale to gunwale (Christensen 1998 ).
The introduction of sail
Despite the widespread use of sail in Gaul and Britain in Roman times, there is little
evidence that Scandinavians adopted this technology before the Viking Age. We find the
earliest confirmation in the Baltic, where Gotlandic picture stones from the eighth
century change from showing rowing vessels to showing ships with sails (Imer 2004 ).
From around ad 800 depictions of sailing ships appear on Viking coins, runic stones and
graffiti, but the Oseberg ship from ad 820 is the oldest find of a sailing vessel in
–– chapter 11 : Viking ships and the sea––