The book that I read was Redwall. The author is Brian Jacques. It was published in 1986.
The major characters are Cluny and Matthios who are animals. The major conflict is that Cluny is attacking Redwall . Matthios has to defend Redwall with many other animals. But Cluny has the bigger army. In order for the animals at Redwall to win, Matthios has to go out to find the sward of Marten the Warrior. Matthios makes lots of friends and finds the sward. At the end there is a huge war which makes the animals at Redwall the victors.
I recommend this book for the kids who like blood and gore. Rats are set on fire and some fall to their deaths. There are many other gruesome deaths. I recommend that you read it too.