Avalon, the 7th Sea analogue to Britain, is a place of myths and magic, a land where the Sidhe still dwell, a race older than human beings but dwindling now. It's made up of three kingdoms - Alvalon, the Highland Marches and Inismore - but all hold the glamour, the mystical nature of ancient Celtic lands. Avalon is a beautiful and terrifying place, legend woven through the fabric of reality.
Chapter 1: The Glamour Isles is the main part of the book, jam-packed with detail on the history (or is that legends?) upon which present-day Avalon is built, beginning with the Sidhe. The islands were united under a single monarch early on, the first king being presented by the Sidhe with an artefact - the Graal - which he was told would provide protection and blessings. Indeed it did until one king in 1028 who had three sons divided the kingdom between them instead of nominating one to succeed him. One son protested and was banished for his pains, the other two fought each other to a standstill with the first son returning from exile to reunite the realm just as the Montaigne turned up and invaded successfully due to the weakened nature of the Avalon forces. Things went downhill with restrictive laws, incessant civil war and a series of monarchs who saw their role as to line their own pockets rather than one of service to the kingdom, with a few shining moments that reminded the Avalonians of what they were and might become again.
Religion caused issues too, coming quite late to belief in the Vaticine Church, but eventually having a rift with them due to a childless king wishing to divorce wife after wife... sound familiar? While it's all a blatant pastiche of real world British history, it has all been twisted around and renamed and recast into something that stands as the Théan version and culminates in the current queen, Elaine, who stands in stead of Elizabeth I but is a unique individual in her own right... although Avalon flourishes under her. We read of lands and titles and Elaine's personal knights, the Order of the High King. This is a body of twelve, with some two hundred at their command maintaining law and order across the kingdom and below them an array of sheriffs, constables and mayors. Then there's a geographical run-down including throw-away ideas than spawn plot ideas if not whole campaigns as you read them. Pity the only map is one of Caerleon, the capital.
So far we have focussed on Avalon itself, but then Inismore and the Highland Marches take their turn - history, gazetteer, culture and more - before we are introduced to the Sidhe. These secretive ancient and mystical magical race are explored in quite some detail that covers much of what makes the whole place so otherworldly. We also get to meet some of the monsters of legend, which are disturbingly real.
Then, Chapter 2: Hero introduces an array of notables to use as NPCs each with a portrait and a description (stat blocks come later in the GM section of Chapter 4). This is followed by Chapter 3: Drama which contains game mechanics - a destiny spread for character creation, rules for the Sidhe (do they even obey rules?), as well as new advantages, new backgrounds, new equipment and skills and new ways to wave a sword around (i.e. new Swordsman schools). There are relevant mechanics for Elaine's Knights, including their oath in full, and if you want to follow the old religion, notes about the Druids. The chapter ends with some magical items.
Finally Chapter 4: Legend is aptly-named, it's all about creating your own legends with a Player Section aimed at would-be players of Avalonian characters giving them ideas as to how to play their characters to effect and even providing pointers and resources to those who'd like to try playing a Sidhe. The GM Section provides stat blocks and background 'secrets' for the NPCs of Chapter 2, along with ideas for bringing Glamour magic and the Sidhe to life in your game and a few monsters.
Whilst living up to the subtitle 'The Glamour Isles' some may find it too derivative, drawing excessively on real-world British history and just changing a few names. I think it does an excellent job of blending reality and imagination to create a part of Théah that fits right into this alternate reality yet feels familiar.