Today, the "Land of Fjords" is one of the richest nations on earth, but until well into the 19th century it was a poor agricultural country, hardly developed because of its rugged mountains and adverse climate. The people subsisted on fish and crops and produced little for the market. Because the king needed iron for cannons, mining began in some places in the 16th century. Kongsberg near Oslo (later "Kristiania") became a mining centre when silver was discovered there in 1623. Copper ore began to be mined in Røros and Løkken in central Norway, and from 1772 cobalt, which was used to dye glass and ceramics blue, was also extracted in Kongsberg. Exports, however, were still limited to wood and "stockfish", the dried cod popular in southern Europe.

The revival of the economy in the 19th century began with an upswing in herring fishing. The processing of fish, especially sprats, developed into a major industry. After the abolition of the guilds and a reduction in customs duties, new businesses were founded: As was so often the case, textile manufacturing was the pioneer, and the first mechanical engineering companies also began operations. Wood processing flourished when paper production from groundwood pulp and cellulose became established.

Shipping experienced a rapid boom from 1850 onwards: shipbuilding expanded and in the capital Kristiania "Akers mekaniske verksted" developed into Norway's largest shipyard.  Maritime trade boomed even more: the Norwegian merchant navy grew rapidly and was the third largest in the world at the turn of the century.

Inland, transport routes were now being developed: On the first railway line, opened in 1854, from Eidsvoll on the southern edge of Lake Mjøsa to Kristiania, the trains transported mainly timber. From the northern end of the lake, where steamboats took over the transport, the line was continued and in 1877 Trondheim, the metropolis in the north, was connected. Important canals were built for the transport of timber by rafts:  The Halden Canal runs parallel to the Swedish border to the North Sea, the Telemark Canal leads from the mountainous region after which it is named via numerous barrages to the port of Skien. To improve coastal shipping, the first steamship of the "Hurtigrouten" was put into service in 1893, regularly calling at Hammerfest at the northern tip of the country from Trondheim.

At the turn of the century, technical progress throughout Europe affected the Norwegian mining industry. The traditional copper mines in both Røros and Løkken switched to mining pyrite (sulphur gravel), which was in demand for the production of sulphuric acid and fertiliser. In Rana, near the Arctic Circle, the enterprising inventor Thomas Alva Edison, with the help of British investors, installed innovative equipment to exploit the vast iron ore deposits. On the southwest coast, the "Titania AS" mined ilmenite (titanium iron ore) from 1916 onwards, from which the paint industry produced a brilliant white. Even in faraway Spitsbergen in the Arctic Ocean, coal mines were opened.

Finally, Norway's most important resource provided the final, decisive push for industrialisation: "white coal", hydropower. A key figure was the Norwegian entrepreneur Sam Eyde. From the end of the 19th century, he secured rights to use waterfalls to generate electricity for new industrial plants. In 1905, with Swedish and French money, he founded what is now known as "Norsk Hydro", which produced artificial fertiliser using its own process even before the invention of ammonia synthesis. To meet the high demand for electricity, Eyde had a huge power station built in Rjukan, where a waterfall plunges 104 m into the valley. In addition to factories for heavy industry, he also built settlements and schools there, so that the place was soon considered a model town. The concept set a precedent throughout the country: by 1920, power plants were springing up all over the place, mostly financed by the state, which wanted to prevent the sale of domestic waterfalls to foreign investors.  The cheap energy attracted energy-intensive industries, especially for electrometallurgy and electrochemistry, and virtually overnight the chimneys started to smoke in the remotest country towns. The production of aluminium and magnesium is still a pillar of the economy today, and hydroelectric power is Norway's No. 1 energy source.

The final step towards prosperity was the discovery of oil southwest of Stavanger in the North Sea in 1969. In the "Ekofisk" oil field alone, 30 drilling platforms were built. Soon other oil and gas fields were developed and Stavanger, until then known for the production of canned fish, became the centre of the oil industry.