A tremendous start – the Sea Stallion and the transport conditions of the Viking Age

Published 08th Jul 2007

It was a splendid sight when the Sea Stallion from Glendalough headed out from the inner broad of Roskilde Fiord. When the crew - with rhythmical shouts - had hoisted the square sail and it began to catch the moderate south-easterly wind, the 30-metre long warship soon broke away from the surrounding fleet of spectator-boats. The few boats that were propelled by oars rather than diesel or petrol were the first to turn back. Neither arm muscles nor small fuel tanks can measure up to the wind as a source of energy when first it is blowing from a favourable quarter. 

As the great square-sail became smaller and smaller behind the island of Elleore, one realised for the first time that this scene was not just a well-orchestrated demonstration for the public but that the undecked vessel with its 25 tons displacement and 61 persons on board had really begun on a long and dangerous voyage, a voyage the success of which would depend not so much on modern norms for materials and safety calculated by engineers but on the seamanship of the crew or - in other words - the ability to make the right decisions in good time and the ability to cooperate and act as one huge organism.

The resolute men and women who headed out of the fiord with a type of ship that has not been used for the last eight centuries were more or less subjecting themselves to the transport conditions that were current in the Viking Age. They are sailing in an authentic reconstruction on a historically known route, propelled only by sail and oars. If the surrounding sand banks and skerries could speak, they would remind us of the many warships and merchant ships that they have seen pass by and be wrecked in the Viking Age. The skipper and the mates on the Sea Stallion have to be content with the three factors that are most prominent on a sea voyage without an engine: The all dominant weather, the fragile ship with its technical limitations and the vulnerable but adaptable crew. The efforts of the crew are the only real variable in this game with the forces of nature. The crew itself is dependent on the steady flow of fresh enough water and food. 

When it comes to the point, it is the supply of water that sets an immediate physical limit to the range of action of the longship. On the open seas there is a long way between the one beverage dispenser and the next. In any case one soon discovers that pure water is the best cure for thirst in this changeable summer weather. Earlier voyages with the Viking Ship Museum’s fleet of Viking ships – including the Sea Stallion’s voyage to Norway in 2006 – have shown that the daily consumption of water for drinking and cooking is at least 3 litres per head. When the Sea Stallion left Roskilde, it had on board 942.5 litres of water in a total of 145 plastic bottles each holding 6.5 litres. Each bottle corresponds therefore to a day’s ration for two persons. That makes 290 daily rations. A crew of 61 can manage with this supply for almost 5 days. This might sound like a short time. If you think, however, that the whole crew when they sailed, lightly dressed and without shoes, weighed 4,825.3 kg, a minimum requirement of 183 kg of water per day (61 persons x 3 litres) is nevertheless quite moderate. 

It is naturally a question of priorities whether one brings one ton or several tons of water on board. There also has to be room for food and equipment. The stewards had a basic amount of food brought in that was sufficient for the first two weeks on board. The space that is taken up by modern things such as life rafts and survival suits would in the Viking Age have been taken up by weapons and armour.

The Sea Stallion had thus a radius of activity of 5 days’ sailing when it set out on Sunday 1. July at 4 p.m. Who among the many yachtsmen present there would have believed that the ship with its crew as yet unaccustomed to being at sea would stick out into Kattegat the very same night and not try to make land before reaching the south coast of Norway near Kristianssand? Here it became clear that the Sea Stallion’s voyage to Dublin is not to be accounted a pleasure cruise. Any family crew would have left the skipper behind on his beloved ship after such a feat in a fresh to hard breeze with gusts of gale force and with showers of rain as the only thing by way of variety. Here the Sea Stallion from Glendalough and its crew lived fully up to the reputation of its archaeological model, the great longship wreck from Skuldelev. The wind-conditions were ideal and the warship therefore just had to sail and exploit the wind to the fine-drawn limit at which the welfare of the rain-soaked and seasick crew become more important to the further progress of the voyage than the propulsion of the wind. 

That the accompanying ship Cable One temporarily evacuated four sick crew members from the middle of the sea – partly to improve the conditions for the crew and partly as an exercise for the difficult situations that may arise – in no way distorts the scientific result. In a similar situation on a longship in the Viking Age they would neither have turned back but continue until the next favourable haven with the sick men on board. The time that was spent with the transfer of the sick people could just of well have been spent in the Viking Age on a necessary repair to the rigging or the rudder.

With its dogged perseverance the crew has achieved the greatest travel speed with the Sea Stallion so far: 240.5 nautical miles covered in 33 hours and 44 minutes. This gives a remarkable average of 7.14 knots (13 km/h) which can be converted to a 24- hour distance of 171 nautical miles (317 km). The Sea Stallion is thus playing in the first league of sailing ships throughout history – up to the middle of the 19th century. 

What did such a travel speed mean in practice in the 11th century? It meant that a powerful ruler in Zealand who had control over men and ships could – after some delay waiting for a favourable wind – land whole companies of heavily armed warriors wherever he wanted in South or East Norway before two days had gone by. These warriors would have been able to seize coastal settlements without warning and hold them for a number of days until a sufficiently large local force could make a counter attack. This scenario of threat would of course also be relevant in the opposite direction, coming from Norway against Denmark. Longships were the speediest form of cavalry that was to be found at that time. The performance of the Sea Stallion reveals one of the preconditions for kings such as Harald Bluetooth and Canute the Great making claim to Denmark and Norway.

Anton Englert, PhD

Created by Anton Englert, maritime archaeologist, curator at the Viking Ship Museum