The Norse colonized Orkney, with Harald Fairhair. Read the history of the colonization from Norway at ://www.orkneyjar.com/history/vikingorkney/index.html. The Earldoms were established about 850 AD.The runes that carry their stories include "Ing", or Ingvarr, meaning phallus, name of a god of fertility and conquering, or also called Yngvi, see ://www.arild-hauge.com/efuthark.htm/ See that site for clicks to runes of individual Scandinavian or Germanic peoples. Or Ingwaz, a rune of harmony. See Learning the Futhark, at http://www.runes.info/pieces/runepiece09.htm
Beginning with 874 AD, then read the list of the rulers of Orkney, fertile or conquering or harmonious, Ings all, in the Orkneyinga, and known as the Earls, at ://www.orkneyjar.com/history/vikingorkney/earls.htm. That list stops at 1231, and another takes over, "the Angus line" until 1321. After that, the Sinclair line 1379-1471, see ://sinclair.quarterman.org/who/earls_of_orkney.html
Events of the earliest times: the Norse took Rouen, France (now) in about 841; and established a settlement at Dublin in 853. Great period of Norse expansion. In 885, the Norse besieged Paris. Read the entire timeline at ://www.orkneyjar.com/history/timeline.htm.
That Orkneyjar website is excellent - hop from one topic to another. Then, read details of the lives and deaths of the Earls (much murder) at http://www.geocities.com/missourimule_2000/earlsoforkney.html.
This brings us to the Orkneyinga Saga, an actual document that lays out the lives of Earls from 900-1200 AD. The places where events occurred are still traceable, and you can follow with your guide pamphlet. The Saga is also in paperback (://www.amazon.com/Orkneyinga-Saga-History-Penguin-Classics/dp/0140443835).
At the Bishop's palace in particular, see the corridor where the assassin ducked into the shadows in front of the group, then leaped in behind the Bishop as he passed, and then ducked aside again. The Bishop, as I recall, immediately struck the man behind him, thinking that was the assailant, and it wasn't.
There are some 14 Saga sites.