Based on texts by Per G. Norseng, Per K. Sebak and Frans-Arne Stylegar

Since prehistoric times, the sea brought together people from near and far. Sails appeared on ships at the beginning of Viking Age (approx. 800 CE), which lengthened cruising range considerably. Viking expeditions were in part launched for raiding and conquest but also for conducting peaceful trade. Moreover, many farmers emigrated to the British Isles or north Atlantic islands.

From the 1300s, foreign ships accounted for most of the contact between Norway and the rest of the world. During the "Dutch era" in the 1600s and 1700s, Norwegian men and women in their thousands made their way to Dutch cities on lumber ships. From there, the men would find work on ships headed to Asia or America. Many died and others stayed behind in faraway places. Norwegians could be found in almost all Dutch colonies, including Nieuw Amsterdam (now New York).

At the same time, seaborne trade between Norway and Denmark flourished. Many Norwegians served in the Danish navy and Denmark-Norway also had colonies overseas. Norway eventually developed a substantial merchant fleet, owing especially to growth in lumber exports. Both Norwegian and Danish ships took part in the slave trade between West Africa and the Caribbean. From the middle of the 1700s until the revolution in 1917, there was considerable trade between northern Norway and northern Russia.

With the increase in global trade during the 1800s, the Norwegian merchant fleet grew and sailed between foreign ports on the world's oceans. Mass emigration began in the 1860s. In addition, Norwegians also became involved in sealing and whaling in distant seas.
Most emigrants travelled to the Midwestern US where land could be acquired at no cost. At the same time, industrialisation in the cities created demand for labour. In the period between 1825 and 1925, around 800 000 Norwegians emigrated. As a share of its population, which was 2.2m in 1900, Norway had the second highest number of emigrants to the US before 1930.

From 1827, steamships ran between Christiania (now Oslo) and Copenhagen, and to Kiel a few years later. In the 1850s, steamship services crossing the North Sea from eastern and western Norway were established. From 1879, it became possible to travel to the US directly from Norway on a Danish line and in 1913 the Norwegian America Line (NAL) was founded.

A considerable share of the male population in Norway in the last quarter of the 1900s travelled abroad as seamen. Norwegian merchant ships still sail the world's oceans, but few Norwegian crewmembers remain. The ocean passenger lines lost customers to airlines through the 1960s. Nevertheless, the level of activity on sea routes to the continent remains high, now with freighters and passenger car ferries.