From June 1940 until May 1945, he oversaw the Norwegian Government-in-exile from London as head of the Nygaardsvold cabinet during the occupation of Norway by Nazi Germany.

King Haakon VII stated that he could not comply with the German ultimatum and would rather abdicate than appoint Quisling prime minister.

He resigned on 25 June 1945 when King Haakon appointed Einar Gerhardsen to head an interim government composed of all political parties.

[7] An Act on 18 June 1938 empowered "the Government to issue regulations dealing with the length of working hours and with medical inspection of workers exposed to X-rays, radium and the radio-active substances.

In addition, under an Order of the 18th of November 1938, the enforcement of the Workers' Protection Act on the State railways has been brought within the competence of the ordinary labour inspectorate".

An Act of the 8th of April 1938 provides that "any company or private undertaking with a share capital or net assets amounting to 100,000 crowns must make appropriations to a Labour Fund.

Contributions are compulsory only when the net profits of the undertaking exceed a certain percentage of its invested capital; the rate varies with the financial results of each business year.

The moneys of the Labour Fund are to be used for payment of old-age and invalidity pensions or for relief of unemployment due to the suspension, transformation or restriction of the work of the undertaking".

Also, in "the event of an accident due to the war and involving permanent incapacity or death seamen are now entitled to pensions and allowances in accordance with the provisions laid down by the Act of 12 March 1937 and the Royal Order of 21 May 1937.

In the event of death his dependants (widow and children under 15 years) receive, in addition to their pensions, a lump sum of the same amount as for permanent incapacity".

Under a Royal Order of 22 December 1939 issued in pursuance of a decision of the Storting of the 15 September 1939, the State made "itself responsible for the risks of persons engaged in sea fishing, including seal hunting and also, to some extent, whaling.

The Act provides for this purpose that the records kept by employers or sub-contractors must henceforward contain, as well as the workers' names and addresses, information on the nature of the work performed and the minimum wages paid.

The investigative commission that issued a report after the liberation of Norway found that he could not be absolved from responsibility for the lack of operational readiness for the German invasion but gave him credit for his management of a unity government in exile.