'Blaufuchs' was a German two-part undertaking to move troops, weapons, equipment and supplies into north Finland in preparation for 'Silberfuchs' (spring/June 1941).

A joint German and Finnish plan, the operation was in fact completed largely by German forces with the primary object of facilitating the capture of the key Soviet port of Murmansk by means of attacks from Finnish and Norwegian territory.

The operational border between the German and Finnish forces was located along a line linking a point to the south-east of Lake Oulujärvi to the Russo-Finnish border and then straight to the east. Eversti Erkki Raappana’s Finnish 14^th Divisioona (division) controlled the southern part of the sector, while the northern part was the responsibility of Generaloberst Nikolaus von Falkenhorst’s Armee 'Norwegen' with Kenraalimajuri Hjalmar Siilasvuo’s Finnish III Armeijakunta (corps) in the south to the north-east of Oulu, General Hans Feige’s XXXVI Corps in the centre to the east of Kemijäarvi, and General Eduard Dietl’s Gebirgskorps 'Norwegen' in the north around Petsamo.

After the completion of its occupation of Norway in July 1940, Germany planned to occupy the Petsamo nickel mining region of Finland in 'Rentier' in the event that a new Soviet-Finnish war broke out. In this regard it is worth noting that Germany had possessed troop and supply transfer rights through northern Finland since September 1940. In January 1941, Oberst (from August 1941 Generalmajor) Erich Buschenhagen, the chief-of-staff of the Armee 'Norwegen', was ordered to Finland to discuss with the Finnish political and military leadership the possibility of a collaborative Finnish and German effort against the USSR. Late in February 1941, Buschenhagen was authorised to negotiate a combined offensive effort. Taking advantage of the co-belligerent pact, plans were made for formations of the Armee 'Norwegen' to start moving into Finnish territory, where they would join Finnish forces currently being mobilised under cover of purported border exercises.

This was undertaken in two phases as 'Blaufuchs I' and 'Blaufuchs II' during June 1941. Five German divisions (Generalleutnant Ernst Schlemmer’s 2^nd Gebirgsdivision and Generalleutnant Hans Kreysing’s 3^rd Gebirgsdivision of the Gebirgskorps 'Norwegen', Generalleutnant Kurt Dittmar’s 169^th Division and SS-Gruppenführer Karl Demelhuber’s SS Kampfgruppe 'Nord' (precursor of the SS-Division 'Nord') of the XXXVI Corps, and two of the three regiments of Generalleutnant Anton Dostler’s 163^rd Division of Generalleutnant Valentin Feurstein’s LXX Corps) were allocated to the command of Kenraalimajuri Paavo Talvela’s Finnish VI Armeijakunta within Marsalkka Carl Gustaf Erich Mannerheim’s Finnish army group) and various attached elements (including the Panzerabteilung zbV 40 and another 'special purpose' Panzer unit) were moved into northern Finland, joining the Finnish forces currently being mobilised under the guise of border exercises.

The Finns and Germans agreed on a three-phase offensive on two axes, and comprising 'Rentier' followed by 'Platinfuchs' against Murmansk, and 'Polarfuchs' to take Kandalaksha on the White Sea and thereby cut the railroad line linking Murmansk with Leningrad and Moscow.