The Northern Isles, which consist of the two island groups of Shetland and Orkney, have been inhabited since prehistoric times but were formally annexed by the Norwegian king Harald Hårfagre in around 875 after he subdued the Vikings who used the islands as a base from which to raid Norway and Scotland.

On the 5th November 1605, the Gunpowder Plot was foiled when Guy or Guido Fawkes was discovered guarding 36 barrels of gunpowder that had been placed in an undercroft below the House of Lords in London.