Following the Swedish defeat in the
Battle of Poltava in June 1709,
Denmark–Norway declared war on Sweden on 8 August (
O.S) that same year. Subsequent
Russian attacks resulted in the seizure of Swedish defense structures across all of the
Baltic region as well as parts of
Finland. The new Russian naval base Kronstadt as well as other newly conquered Baltic ports became bases for Russian vessels. This drastically changed the situation for the
Swedish Navy, as they had to focus more on the growing Russian Navy, compared to before, when the Swedes had concentrated their efforts on the Danes in the southern
Baltic Sea and
Øresund. The vital objective was to prevent the Danes and Russians from coordinating and combining their naval power. This situation was a major strain on Swedish resources and it made the defense of their western waters from the Dano-Norwegian fleet especially difficult. The Gothenburg area was considered a relatively low priority, despite the fact that the city's trade significance was growing. . The construction of a new, deeper naval base,
Nya Varvet (
New Yard), had begun in 1700 at the river entrance of
Lilla Billingen, which was supposed to replace the existing
Gamla Varvet (
Old Yard), at what is today Stigberget. By spring 1715, 72 of the 140 naval officers that were conscripted in Gothenburg were ordered to Stockholm and the navy in the Baltic Sea. In order to compensate for the Swedish navy's diminished resources,
letters of marque were issued, which authorized crews of armed, privately owned Swedish vessels to seize vessels belonging to nations that Sweden were at war with, and to an extent, sell their cargo. The crown received a 10 percent cut on these sales. Starting in 1710, privateering companies were being set up as a result. In 1711, the Crown allowed loyal privateers to borrow weapons and munitions from the government's Gothenburg storages. Admirals complained that privateers were using conscripted sailors during their operations that were supposed to be serving in the Navy. Swedish privateering operations expanded further in 1715 when foreign navy captains were authorized to receive letters of marque and to operate under Swedish flag. It was also no longer mandatory to pay a cut of the cargo value to the Swedish crown. By 1715, a total of 25 Swedish privateers were conducting active operations in the Western Sea, which disrupted Dano-Norwegian trading routes severely. The largest privateering operation was led by
Lars Gathe of
Onsala. He was named Gathenhielm and Commander by
Charles XII so he could not only command his privateering operation, but also the entire Swedish privateering fleet on the west coast.
Charles XII's Norwegian Campaign of 1716 1716 (green line), and
Fredriksten 1718. Locations displaying Dano-Norwegian counterattacks 1716, 1717 and 1719 also shown. In February, a smaller Swedish force composed of men from
Värmland,
Dalsland and
Svinesund, marched into Norway with the intention of conquering
Akershus fortress in
Christiania, thereby forcing Denmark to make peace. After passing by the fortress town of
Fredrikstad as well as
Fredriksten fortress, near present-day
Halden, Charles XII was able to march in to the undefended Christiania by 11 March, whilst under persistent fire from Akershus fortress. After a failed storming attempt, Charles XII realized that he needed access to more powerful siege artillery. Repeated attempts to defeat the Norwegian forces around Swedish-occupied Christiania failed because of General
von Lützow's skilled defensive tactics and by him avoiding as many battles as possible, since he was aware that his relatively untrained army couldn't compare to the seasoned Swedish
Caroleans. Additionally, the coming thaw meant that Danish reinforcements could start arriving by ship. The rough Norwegian terrain, combined with the lack of supplies and the active resistance of the local civilians forced the Swedish army to retreat south. A major cause to the Swedish defeat during the campaign was the inability to compete with the Danes on the sea. The commander of the Gothenburg Squadron,
Vice admiral Axel Lewenhaupt, had only managed to put one frigate, the
Älvsborg (46 cannons) to sea, by letting privateers borrow it for 20 000 daler. This, of course, did not prevent Danish vessels from supplying the Norwegians with soldiers and supplies. The Danish General Staff credited the retaking of Christiania to their fleet. In Gothenburg, Vice-Admiral Lewenhaupt had under rough circumstances managed to put together a transport fleet consisting of 24 vessels loaded with siege cannons, ammunition and other supplies. The fleet was escorted by six
galleys and an armed
barge. It moved slowly north along the coast under the command of
schoutbynacht Olof Knape. By the end of April, it entered
Dynekilen, a
fjord between
Strömstad and
Svinesund. Additional transport ships arrived during the following months.
Battle of Dynekilen During the night of June 28, Norwegian Commander
Peder Tordenskjold initiated one of the most daring and most widely renowned naval battles in
Nordic history. By sailing directly into the approximately 5 kilometer long and narrow fjord with
frigates, galleys and armed barges, the Swedes were taken by surprise. The Dano-Norwegian superior number of cannons meant that the entire Swedish transport fleet was either sunk or captured after five hours of combat. Without any usable siege artillery, and with a high risk of being cut off, Charles XII ordered a full retreat of the Swedish army on June 29. His soldiers managed to cross over to the Swedish side of the
Idefjord, before Tordenskjold could destroy the bridge at Svinesund. The 25-year old Tordenskjold was promoted to
captain, and in November he was designated Chief of the Norwegian Navy. The Swedish captain Strömstierna managed to reach land from the galley
Wrede, and despite his defeat, he was promoted to vice admiral by Charles XII. By early 1717 the Danes were still worrying that Charles XII would resume his invasion of Norway. Swedish privateers based in Gothenburg were still persistent in their harassing of Dano-Norwegian trade. Tordenskjold therefore prepared an assault on the Gothenburg Squadron and as much as possible on the Gothenburg-based privateering squadron at
Göta älv. The moment of surprise would gain significance, as it did at Dynekilen. There were however no plans on attacking the Nya Älvsborg fortress or the Gothenburg city fortress. By February, Danish vessels had started blockading the river mouth of Göta älv. == 1717 Attack on Nya Varvet ==