It may behoove you to read the previous book in this series, Redwall
Mossflower, technically the second book in the Redwall series, serves as a prequel to the eponymous book, and is one of the earliest books in the series, chronologically speaking. It is the book that details the conquest of Martin the Warrior, the famous warrior/founder of Redwall abbey, from which the series takes its name. It’s also the first book in the series that I ever read, my brother having recommended it over Redwall.
Mossflower opens with the arrival of Martin the Warrior in Mossflower wood, where a tyrannical Wildcat known as Verdauga keeps the woodland animals in a sort of serfdom. Cruel but fair, the situation has lead to a tenuous—if difficult—peace the inhabitants of the area, who were once ruled by a badger lord. When Verdauga’s daughter, Tsarmina, poisons him and imprisoned her phlegmatic brother, things go from bad to worse, and open rebellion is fomented among the woodlanders. Needless to say, Martin the wandering warrior rubs Tsarmina the wrong way, and there is a lot of general hating going on.
While I always thought that Redwall was a comparatively rough book, being the first of the series and predating any sort of serious canonization, it is really with Mossflower that I think Jacques finds his groove, settling into the tropes which will serve him well for the next 20 or so years (lord have mercy, has it been that long?).
It seems as though Jacques really caught his momentum with this book—some of his most endearing characters are in Mossflower—and began to build out his canon, realizing, I suppose, that he was not merely the author of a single autonomous novel (Redwall), but an entire world. In Mossflower comes Salamandastron, the mountain home of badger lords and fighting hares; the famous sword of Martin the Warrior is forged, sea rats are killed, the refugees from the distant abbey of Loamhedge foreshadow the eventual building of Redwall Abbey.
This particular book to this day remains one of my favorites in the series, despite the stiff competition.