Sten Allan Olsson (1916-2013), founder of Stena, was one of the greatest Swedish maritime entrepreneurs and shipowners, along with Dan Brostrom (1870-1925) of the large Brostrom Group of Gothenburg, and Sven Salen (1890-1969) of the equally big Salen Group of Sweden. Sten Allan Olsson was born on 28th October 1916 on the small island of Donso in the Gothenburg archipelago as the son of Gustav Olsson, the owner of a small trading schooner. He was educated at Ljungskile Folk High School, followed by a commercial course at a college in Gothenburg. Sten learnt the entrepreneurial basics from his father of hard work, close long term family links, responsibility, thrift, and the transport, buying and selling of goods and services at very good profits. The charter market was very important for Sten, with classes of ro-paxes and freight ro-ros specifically ordered for charter to worldwide clients, and this was extended later into the purchase and chartering out of older second-hand ferries for use as accommodation ships for North Sea oil workers or for workers on industrial projects in remote Scandinavian locations where large hotels were not available. The many classes of new ro-paxes and ro-ros on the main routes from Sweden, Denmark, Germany or Northern Europe made Stena into the largest ferry line in the world.

On 18th November 1939, Sten Allan Olsson founded his Metallproducter trading business in Gothenburg, consisting of a large scrap steel yard and supervised from a two storey metal clad office. The yard was located behind one of the great shipbuilding yards in Gothenburg harbour, and scrap steel, boilers and rubber products were in great demand from his fledgling business for the shipyard during World War II. In 1946, he purchased his first ship with a loan of 25,000 Swedish kronor from the Handelsbanken. This was a three masted schooner named Dan after one of his three sons, Dan, Stefan and Christofer, born after his marriage to Birgit Andersson in 1944. The schooner was traded in the scrap metal, timber and general cargo trades of the Baltic. She was the first of a dozen owned small motor coasters and a dozen similar chartered coasters, that formed the Olsson fleet during the 1950s. The coaster Stefan of 497 grt, built in 1955 by the Solvesborgs Varv yard in Southern Sweden was the first newbuilding in the fleet, and had a very long career after her sale by Sten, and was still afloat 45 years later in Greece as Santa Maria. The Metallproducter business in 1952 opened a separate branch for metal collection and processing at Hisingen near Gothenburg, which is still in business to this day as a major recycling company.

Sten Allan Olsson moved into the passenger transport trades in December 1962, when a chartered small passenger ship set sail from Gothenburg to Skagen in Denmark. This was the chartered Bornholm ferry Ostersoen, but the ice was too thick on the Kattegat during the winter and this charter was quickly ended. In the Spring of 1963, he took over the Skagen Line passenger service on the same route with the small twin decked steamer Brynhild of 937 grt, built in 1914 as Heimdal by Burmeister & Wain at Copenhagen also for service to the island of Bornholm from the mainland. She was of overall length 209.6 feet, moulded beam of 34.2 feet, and moulded depth of 18.6 feet, and could carry 350 passengers at a service speed of 12 knots from a triple expansion steam engine by her builders for island service. She was renamed as Skagen I, and was then purchased in 1964. The running mate of Skagen Line was a former Gotland island steamer built in 1924 by the Oskarshamns yard as the twin decked Visby for Rederi A/B Gotland, renamed Skagen II of 799 grt and overall length 171.2 feet, moulded beam of 30.5 feet, moulded depth of 13.7 feet with a service speed of 12 knots from a triple expansion steam engine by her builders.

Skagen I was used in the 1964 summer season for a service from Lysekil to Skagen and then sold in 1965 and converted into a barge. Skagen II continued the successful, rapidly expanding Kattegat service until broken up in 1968, along with chartered excursion passenger ships such as Wappen von Hamburg, which was also purchased, Seute Deern, Seebad Warnemunde, Hein Goden-wind and Helgoland of 2,855 grt, built by the Howaldtswerke yard in Hamburg in 1963, from German owners. Helgoland served as a hospital ship in Vietnam between 1966 and 1972 and was then purchased by Stena and renamed Stena Finlandica. She was sold in 1975 and renamed Baltic Star, and started a new career in 2001 as Galapagos Legend.

Much publicity was gained from the visit of President Nikita Khrushchev, Soviet Union leader from 1953 to 1964, to Gothenburg in 1964 to visit the big Arendal shipyard in the harbour as well as a tour of the city. He travelled around the harbour on the newly completed Stena passenger vessel Poseidon of 1,364 grt from the Ulstein Mek Verksted yard in Norway. She was also to take President Khrushchev and his family on a cruise from Uddevalla to Gothenburg, but this did not happen. Poseidon was yard number 26U with accommodation for 600 passengers with a service speed of 16.25 knots from a Deutz diesel engine of 2,640 bhp. She had an overall length of 65.5 metres and a moulded beam of 11.6 metres, and left the fleet in 1972 on charter to Brittany Ferries for the Plymouth to Roscoff route. After a long career of 42 years, she was broken up in India in 2006. A similar newbuilding passenger ship to Poseidon was also completed as Afrodite at a yard in Elmshorn in 1964.

The sisters Stena Danica and Stena Nordica of 2,607 grt were completed in 1965 by the Le Trait yard of Ateliers et Chantiers de la Seine Maritime as the first purpose built Stena car ferries. They had large funnels and were twin screw motor vessels fitted with Klockner Humboldt Deutz diesel engines to give service speeds of 17.5 knots. They could accommodate one thousand passengers with 129 cars and 14 lorries on their vehicle decks. After Stena Danica joined the Gothenburg to Frederikshavn route in June 1965, a different strategy was used for Stena Nordica for a new summer passenger and car Tilbury to Calais service as ‘The Londoner’. She was displayed to the British press in July 1965 on the Thames with ‘THE LONDONER’ in red capitals on both sides of her hull. She was then chartered for the 1966 season for the Stranraer to Northern Ireland service of the Caledonian Steam Packet Company, with a chartered vessel, Prinsessan Christina, on ‘The Londoner’ service in 1966, and the new smaller twin funnelled Stena Baltica of 1,200 grt from the Langesunds yard in Norway in 1966 and used in the last 1967 season of ‘The Londoner’. Stena Baltica was sold in 1970, Stena Danica was sold in 1969, and were replaced by the sisters Stena Germanica and Stena Britannica of 5,195 grt from the Langesunds yard for a new Gothenburg to Kiel service. Insufficient traffic forced Stena Britannica on to the Gothenburg to Frederikshavn for a few months until her sale to the Alaska Marine Highway to run as Wickersham in 1968.