In 1469 the Orkney and Shetland archipeligoes were pledged as security for a dowry by Christian I of Denmark and Norway to James III of Scotland. The islands eventually became part of Scotland proper. Why did Christian not pledge the Faroes also?
I outlined the pre-modern history of the Faroe Islands since the settlement by Norse-speaking people before in: How did the Faroe Islands get into the hands of the Kingdom of Denmark? Is it a colony or constituted as something else?
In contrast to the Shetlands (see also my previous post in: Has there been any Shetlanders of note in history?), Faroe Islands constituted an quasi-independent political community at least from the Earldom of Orkney that generally incorporated the Shetlands, and the kingdom of Norway annexed these Islands in the North Atlantic in different timings.
It is also worth remarking that the Faroe and Orkney-Shetland Isles did not largely have a political history in common at least until about 1200.
To give an example, we don't know any notable Faroe Islander who took part in the rebellion of the Øyskjegginger against King Sverre of Norway (himself had been in the Faroe Islands) between 1192-94, in contrast to those who came from the Orkney and Islands (probably secretly instigated also by Earl Harald Maddadson of Orkney) (Krag 2005: 141-44).
After the incorporation into so-called "Norwegian Dominion", Norse-speaking colonies of the kingdom of Norway, the Faroe Islanders apparently kept their own Althing at least in the High Middle Ages, as the Icelanders did (Sanmark 2017: 174-83).
The Faroe Islands had also constituted a distinct bishopric since the middle of the 12th century.
Thus, they should not be counted as a kind of appendix to the Orkney Islands, I suppose.
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