From the Sagas we learn that the aim of every chief was to be powerful at sea; every bondi was owner of one or more craft. They were born seamen, but were also trained to fight on land. They surrounded themselves with warlike retainers, and with these made distant expeditions to win honour and booty. These men were also soldiers, and good horsemen. As we see that in every great land battle the warriors came from all parts of the Northern lands, it must be concluded that the same took place in regard to their invasions of foreign countries. Only in a very few instances have we accounts of the Norsemen being defeated at sea by the fleets of the countries they attacked; even in these rare instances their combats took place with a very small number of vessels compared with the powerful fleets of their enemies, who were either Frisians or their own people who had settled in England.
Fortunately, Frankish and old English chronicles, which are quite independent of those of the North, help to corroborate the general truthfulness of the Eddas and Sagas, and from them we have several accounts of the number of vessels which sailed up the Seine, the Rhine, the Elbe, and the Weser, or went to England.
The largest fleet that ever met in the North was that which assembled for the battle of Bravöll; though the number of vessels is not mentioned, we read that the Sound was covered with vessels. This fleet reached from Kjöge to Skanör, so that, if the account is trustworthy, people could walk as on a bridge from Zeeland over the Sound, a distance of some twenty miles. Sigurd Hring had 2,500 (3,000) ships to oppose him.[[147]]
The maritime expeditions of the Northmen to distant lands were undertaken with a great deal of care and foresight; the men were under strict discipline, and were attired with the greatest splendour. It would be a mistaken idea to think that the Northmen started on these voyages without any previous knowledge of the country they were to invade, or of the shores where they were going to land, or that they sailed with no definite object. Their previous knowledge of these far-off lands was no doubt gained in trading, and it was only after being thoroughly well acquainted with the geography of the part to be attacked that they ventured on their invasion.
Many of the places in foreign countries mentioned in the Sagas where the Norse fleets were safely moored and sheltered against storm, are to this day good harbours, and if others are no longer so it is because the shores of those coasts have been subjected to changes which are still taking place. The geographical positions of the rivers they ascended were well chosen; they knew what size of vessel to take there, and though their operations seemed to be detached, we find that their fleets were in communication with each other, and that their armies could assist one another in case of need, crush the enemy between the rivers they had ascended, or between them and the sea. In a word, their tactics showed considerable boldness and strategical skill, which generally left them a way of retreat, if necessary, to their vessels or to some island. Though the Sagas give us a good and vivid idea of the Norse mode of warfare at sea, they are very incomplete in regard to the description and details of the land expeditions, and we have to go to the Frankish chronicles in order to see the manner in which they attacked or besieged a city. From these we learn that the ships ascended the rivers as far as possible; if anything stopped the navigation, a canal was made or the vessels were drawn along the shore, and the obstacle thus passed. The Norsemen took possession of all the large islands, fortified them, and wintered there; and there they kept their spoils of war or plunder. They also brought cavalry in their ships, a fact proved by the Bayeux tapestry.
It is said that Harald Blátönn (blue tooth) went to Norway with a fleet of 700 (840) ships.
“Then King Harald summoned a host from his entire kingdom. Hákon jarl was with him, and Harald Grænski, son of Gudraud Björnsson, and many other powerful men, who had fled from their estates in Norway on account of Gunnhild’s sons.
“The King of Denmark sailed from the south into Vikin with 700 ships,[[148]] and there all the inhabitants came under his rule; and when he reached Túnsberg, large numbers gathered to him.
“King Harald gave to Hákon jarl all the men who had come to him in Norway; and made him ruler over the seven fylkis of Rogaland, Hördaland, Sogn, Firdafylki, Sunnmœri, Raumsdal, Nordmœri”[[149]] (Olaf Tryggvason, c. 24, 2 Fms. I.).
Knut the Great had gathered a fleet of 1,200 vessels[[150]] for an attack on Norway.