The history of civil aviation dates back to the late 1910s. Some of the well-known international airlines of today were founded at this time. Dutch KLM was formed in 1919 and Finnair (then Aero OY) in 1923.

In 1946 Scandinavian Airlines System (SAS) was formed by the amalgamation of AB Aerotransport (ABA),Det Danske Luftfartselskab (A/S DDL) and Det Norske Luftfartselskap (A/S DNL). The background to the formation of a joint Scandinavian airline was the realisation that the international market for each individual company was limited. By co-operating it was presumed that the Scandinavian countries would be able to provide an international air network from Scandinavia with Köpenhavn as the operative base.

AB Aerotransport (ABA), which was formed in 1924, was the only Swedish airline that, up to the end of the Second World War, had a licence for scheduled services and operated both European and some domestic services. In 1943 the wholly privately-owned Svenska Interkontinental Lufttrafik AB (SILA) was established to operate services primarily to North America. The SAS consortium was formed in 1951, retroactively from 1 October 1950. As early as 1946, however, SILA had begun to collaborate with Norwegian DNL and Danish DDL. This collaboration was on the Atlantic routes and took the form of a consortium called OSAS (Scandinavian Airlines System, Overseas Division) When SAS was formed in 1951 these services were taken over from ABA and SILA. These company names survived because it is SILA and the Swedish state that each own 50% of ABA, which in turn owns 3/7 of SAS.

Before Linjeflyg was formed in 1957, most domestic services in Sweden were operated by SAS, but by present-day standards the network was very under-developed. The frequency of flights on the main routes was not very impressive. In 1953 SAS flew two flights per weekday between Bromma and Göteborg and one flight per weekday between Bromma-Luleå and Bromma-Malmö. The planes were DC3 and Swedish-built Scandias.

Linjeflyg was formed because it was feared that the domestic services would be cut in the early 1950s owing to several of the SAS lines not being as successful as anticipated. Instead of closing down domestic lines, however, SAS presented a plan to the government in 1955 for the development of regular services within Sweden. The needs of other lines than the main routes were considered to be better served by other planes than those SAS had at its disposal.

In 1958, one year after the formation of Linjeflyg, only 14 towns were connected to the domestic network. SAS operated the main routes (Stockholm-Göteborg-Malmö-Luleå-Kiruna); other regular domestic lines were operated by Linjeflyg. Progress was rather slow in the 1960s. Gradually new airports were added to the domestic network. By 1965 seven new towns had been added. An interesting development was that routes had been established outside Stockholm. Linjeflyg operated a route between Göteborg and Sundsvall via Karlstad and Borlänge. Malmö had direct connections with Göteborg and Visby via three airfields in south-west Sweden. The route to Nordmaling Airport had been transferred to Umeå. From the mid-1960s Linjeflyg began to introduce Convair 440 Metropolitans into its fleet. This plane was to become a faithful retainer in Swedish domestic aviation.

By 1976 almost all the towns on scheduled routes had direct, non-stop connections with Stockholm. In the mid-1970s Linjeflyg introduced its first jet plane, the Fokker F 28, which later became the dominant plane on domestic routes. All in all 26 towns had regular scheduled services by 1976.

Even though Bromma Airport was more attractive for passengers flying to Stockholm, the problem of noise and the time-consuming transfer between domestic lines at Bromma and international lines and the SAS domestic lines at Arlanda were obvious disadvantages. So the domestic lines were gradually transferred to Arlanda.

Arlanda was first used for intercontinental traffic in 1960 and for all scheduled international flights in 1962. SAS domestic traffic moved to Arlanda in 1969 after the introduction of jet planes had made it impossible to continue flying from Bromma. The transfer of Linjeflyg´s traffic and most of the secondary lines to Stockholm from Bromma to Arlanda in 1983 encouraged the expansion of aviation. Other positive factors were regional policies designed to reduce the long travelling times between Sweden´s central places and those on the periphery. Both locally and regionally large investments have been made in airports for scheduled domestic flights. The aim is to increase these towns´ accessibility by linking them closer to the national and international air network .

The traffic pattern is centred on Arlanda. Few cross-country lines exist since most potential routes of this type would be difficult to operate at a reasonable profit. Another explanation is that aviation policies have not encouraged such cross-country links. Developments in many countries have favoured hub-and-spoke networks, since passengers are considered to get better service in the form of more frequent departures with good transfers in a concentrated network. Concentration of the network of lines on one airport also facilitates effective operational use of planes by the airlines.

There are more statistics on the Board of Civil Aviation´s home page.