The uncrewed Spectrum rocket was the first commercial flight to reach orbit from continental Europe, where several nations have said they want a share of a growing market for space missions.
"We're in orbit! And just made European history," Isar said in a post on the social media platform X.
The event was a breakthrough for the European launch industry, giving the continent better access to space, Norway's minister of industry and commerce, Cecilie Myrseth, said in a statement on Saturday.
"The fact that we can now launch satellites from Andoeya strengthens Norwegian and European security in the turbulent times we live in," Myrseth said.
German Chancellor Friedrich Merz visited Isar's launch site in March, underscoring Europe's efforts to establish greater autonomy as the global order once championed by the United States is shifting under US President Donald Trump.
Blasting off from Norway's Arctic Andoeya Spaceport, the uncrewed Spectrum, designed for small and medium-sized payloads, carried five small satellites as well as an in-flight technological experiment, according to Isar.
It was Isar's second launch, coming 18 months after the company's first rocket plunged into the sea and exploded in a fiery spectacle shortly after takeoff from the same site.
The March 2025 launch was nonetheless deemed a success by the company for generating large amounts of data for its developers.
Saturday's launch was intended as "both the vehicle's qualification mission and its first flight carrying payload," the company said.
Global players in the satellite launch market include Elon Musk's SpaceX, which launches from the United States, and French ArianeGroup, a joint venture between Airbus and Safran that uses a spaceport in South America's French Guiana.
SpaceX, a company spanning rockets, satellites and AI, in June listed on the Nasdaq exchange in a record initial public offering.
Sweden, with its Esrange launch site, and Britain with its SaxaVord Spaceport in the Scottish Shetland Islands, are the nearest rivals to the Norwegian site, all of which aim to give Europe greater autonomy in space flights.
Isar last week said it had secured about 200 million euros ($A323 million) from the European Space Agency to help fund development of new rockets and expand its testing and launch infrastructure.
The German company is also developing a second launch site in Canada.
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