For reading to him there's "Eagle of the Ninth". I think there's also a "My Story" one (my ds, also 5yo likes the My Stories) which is generally done in the form of a diary, whic is quite good for them to follow.
Can anyone recommend any books on roman soldiers or just soldiers for my DS who is 5. He is in a play as will be playing a roman soldier but now he would like to read some more stories with roman soldiers or just soldiers in it. Any suggestions? Thanks