A community of Helvetii Celts finds itself lost within the realm of Equestria in a last ditch effort to escape the waves of destruction brought on by the legions of Rome. With no known way to return home, they must find their place in this new and strange world, and earn the love and trust of its denizens through trials and tribulation like no other.

Deep in the Royal Canterlot Archives lies a book that hasn't seen the light of day for longer than any pony could remember. Its uncovering reveals powerful magic as old as the Princesses, and tells stories of heroes and villains long dead. Twilight will find that this book is much more than just an ark of ancient magic, it was meant to be found...

In ages long gone, a race of war-like ponies threatened the lives of all who could call themselves Equestrian. Stumbling upon an old reference book, Twilight discovers the true nature of these old ponies, and witnesses the fate of the world change forever.

One thousand years later, the mortality-defying guardspony, Warden, has returned to his place at Luna's side. He has traveled a rough path, but he has barely glimpsed the lengths of the longest journey that awaits them...