In 1959, the s/s Viking was the first genuine car ferry to begin service for Viking Line between the Finnish mainland, Åland and Sweden.

On June 1, the vessel undertook its maiden voyage on the Galtby (Åland)–Mariehamn (Åland)–Gräddö (Sweden) route. The vessel was owned by a newly established company, Rederi Ab Vikinglinjen, in Mariehamn. The ferry was 99 metres long and had a capacity of 88 cars. One week later, the Swedish–based company Rederi AB Slite began ferry service between Simpnäs (Sweden) and Mariehamn with the Slite, a cargo vessel rebuilt into a ferry.

Revolutionary expansion

Many people viewed these new ferry ventures with great scepticism, but they later realized that this was the first phase of an almost revolutionary expansion in ferry communications between the Finnish mainland, Åland and Sweden. Before the ferry epoch began, it was expensive and difficult to travel between the Finnish mainland, Åland and Sweden. People either had to fly or take a night boat that made a detour to Mariehamn during its voyage between Turku and Stockholm. This was both an inconvenient and an expensive trip. Taking along your car was no unproblematic enterprise–cars had to be hoisted on board. This meant a major risk of damage. As for cargo, big rig truck drivers had to drive north all the way around the Baltic Sea via Haparanda when they wanted to transport freight between Stockholm and Helsinki, for example.

Easier and cheaper travel

The newly established service signified a long-awaited transport upswing. Many people's dream of taking their family on a car trip between Finland and Sweden at a reasonable price became a reality. This was because ticket prices were low. A democratization of travel had occurred. Now it was not only the affluent who could afford a trip to their neighbouring country. Cars no longer had to be hoisted on board. The s/s Viking, for example, had a ramp that both cars and trucks could use to drive on board.

Viking Line launched its ferry service under favourable external circumstances. The post-war travel and currency restrictions that had previously hampered development were gone. A passport union among the five Nordic countries made travel unbureaucratic. The establishment of a single Nordic labour market stimulated flows of migration. Economic growth generated a greater need for cargo service and led to a new phenomenon, mass car ownership. Combined with the opportunity to buy duty- and tax-free goods on board, this created favourable preconditions for rapid volume growth in both cargo and passenger services.

In 1960, Vikinglinjen moved its destination port in Sweden from Gräddö to Kapellskär. In the company's judgement, Kapellskär had a more strategic location as the starting point for ferry traffic to the Finnish mainland and Åland.

At Rederi Ab Vikinglinjen, there were different opinions as to whether the company should focus on pure ferry services or on ferry traffic combined with dry cargo and tanker vessels. In 1963, the advocates of a pure ferry service established the shipping company Ålandsfärjan Ab, later SF Line Ab and now Viking Line Abp. The same year, this newly established shipping company placed its own vessel, the s/s Ålandsfärjan (Swedish for The Åland Ferry) In service for Viking Line on the route between Mariehamn and Gräddö, later Kapellskär.

Co-operation begins

Although many people had initially been sceptical of the ferry services, it was not long before others realized the potential of this new industry. The ferry service pioneers soon found that they had imitators. Competition heated up and price wars occurred. People spoke of "suicidal prices" and "the big ferry price war".

Market players soon realized the usefulness of co-operation between the shipping companies. As a result, Ålandsfärjan Ab, Rederi AB Slite and Rederi Ab Solstad (formerly Rederi Ab Vikinglinjen, owned by Rederi Ab Sally) began a marketing collaboration.

The marketing company Vikinglinjen Ab Oy, later Viking Line Marketing Ab Oy, was established in the autumn of 1966. The red colour was introduced as early as 1965 by Rederi AB Slite on the M/S Apollo.

Service expands

The year 1970 is usually called a milestone for Vikinglinjen. Firstly, three newly built vessels based on extensive fresh thinking were delivered. They were all built to meet the highest Scandinavian standards, with special emphasis on comfort and service to passengers. Secondly, the road to the ferry terminal in Kapellskär was promoted to European Highway. This implied that the car ferries became a natural continuation of the highway, with the same European Highway status.

The cruise epoch

During the 1970s and 1980s, car ferry services rapidly evolved from the traditional car ferry concept to the luxurious cruise ferries of today, which satisfy a wide variety of customer needs, such as pleasure cruises, conference cruises, one–way passenger travel and cargo services. Meanwhile the route network gradually expanded to include Naantali (later Turku) and Helsinki as destination ports in Finland, as well as Stockholm on the Swedish side. Late in the 1980s, cruise services to Estonia also began. After Estonia’s entry into the EU, this service was boosted by new investment in frequent, regular passenger, vehicle and freight services.

Rederi Ab Sally and Rederi AB Slite left the Viking Line consortium in 1988 and 1993, respectively. In 1993, the current Viking Line Abp became the parent company of the Viking Line Group. In 1993 the current Viking Line Abp company became the parent company in the Viking Line Group. In 2005 the marketing company was merged into the parent company.