Being a resident Scot myself, Cthulhu Britannica and, especially, Shadows over Scotland were always going to be of interest and appeal to me. The first section of the book is a look at 1920's Scotland and the mood of the people, recent history including the role of the great war, what life is like for the different classes, politics of the period while also taking care to look at the positives of the time like in creative arts such as the works of Charles Rennie Mackintosh, the success of J.M. Barrie and other literary works. Neatly, there are also sidebars for pre-decimalisation money (though oddly it doesn't specifically say it was 240p to the pound, the closest it gets is saying it was 12p to the shilling and 20 shillings to the pound) and some common Scots lexicon/lingo (with pronunciation guides for things like ceilidh and the sgian dubh) to help add a more authentic edge to dialogue.

Next we come to the Keeper's History of Scotland, covering Scotland's history in about 10 pages from the prehistoric and stone age, moving onto the ages of bronze and iron, Roman invasion of Britain (including a possible Mythos explanation for the disappearance of the Ninth Hispanic Legion) before moving to the rest of the first Millennium – Picts, Celts, Vikings, Angles and the conflicts between Mythos and Christianity. We then take a look at 1000-1500; the unification of Scotland under one rule and Edward I's attempt to claim sovereignty over Scotland and the Declaration of Arbroath. Next is 1500-1750 covering Mary Queen of Scots, her exile, religious reformation and Union of Parliaments, Jacobite rebellion (and a sidebar on the Glencoe Massacre), Industrial Revolution and Early 20th Century. And all this before we even get to the Mythos Timeline! The mythos timeline covers the whole period from Pangaea to 1920, giving the key events of Scotland in order with some of the non-Mythos events to help us piece it all together more easily and Shadows over Scotland then introduces us to about half a dozen notable figures of the 1920s including Alexander Fleming, Arthur Conan Doyle and also has a list of suggested further reading for more information on modern Scotland, the history and people that have made it up.

With the scenarios provided, there's a lot of interesting different ideas – some classic figures of Scottish history converted into Mythos beasties that'll still be around in the 1920s and possibly later still, some classic beings used in others and across a wide range of locations in Scotland. I've only ran one of the scenarios - The Forbidden Isle, set on the island of Rum – and reading through it I was excited. A fairly straight forward scenario that should work well for a group that was made up of players who had played Cthulhu several times before and others who had never touched it. It looked interesting and taking a quick look on google for extra research it seemed to be a well researched adventure and well laid out. Reading through it, there were some details I wish I'd paid more attention to when it came to running the adventure; red herrings that distracted the party and details they did notice (and some they didn't) that I simply didn't have an explanation for even after the scenario was finished (such as missed footprints in the dust in the attic that lead to a pile of clothing implied to belong to the victims – how did it get there? Was it the enthralled servant of the Mythos creature, was it a member of the household, was it coincidentally similar? I still don't know and I'm glad the party missed two sets of spot hidden rolls so I didn't have to explain that or have the party become more convinced it was some sort of inside job). It left me disappointed in the end, something I hate to say about an otherwise fantastic book.

Overall I'd say the book is solid – excellent background and characters. It could practically be an engaging, well written textbook for the information it has on Scotland and it's history. I've only ran or played one scenario, so I hope it's one of the lesser scenarios as it left me a little disappointed but there are still fantastic ideas for games and scenarios. I'd rate the book 5/5 – the information could possibly rival an academic book on Scotland and it has lots of good ideas but I feel the scenarios are disappointing without a lot of careful reading and note-taking to find out what are genuine clues, red herrings and how the red herrings can be explained if discovered after the scenario is over.