I have to agree with Shane, you have to be very careful of Angus McBride's work if you're concerned with accuracy. He's perhaps best known for his collaborative titles with David Nicole and in these cases Dr. Nicole should be the one determining the accuracy of the finished illustrations and sometimes that's the first problem. Like any academic he lists the primary sources from which the various elements are taken, but sometimes they are so extremely disparate that putting them together on a single figure can give results that are frankly little better than guesswork an educated enthusiast would make.
Additionally, McBride adds his own touch to many pictures to make them better paintings - to make them look good - possibly with an eye to having the original sell, but regardless of the motivation from our point of view this is very dangerous. Sometimes this is something as subtle as his choice of colour but not infrequently it's much more serious. There are numerous examples but I'll stick to a favourite: round shields. If you look at his representations of them in use by various European cultures they are rarely depicted as completely flat - I personally suspect purely because this makes them more aesthetically pleasing when seen in 3/4 profile - when, if you do your own research, the evidence suggests they were mostly just that (until eastern influence began to be a factor most likely). Three titles to compare would be The Vikings, The Age Of Charlemagne, and Arthur And The Anglo-Saxon Wars. The first of these is the best in this regard, possibly because the author, Ian Heath, made a point of having the shields be flat; but take a look at the edge of the shield in the foreground figure on plate F, in addition to being slightly domed the edge looks like it's around 2cm thick!
And to top it all off you have to consider McBride's age, he's 73 now, and his later work is often a mere shadow of how good it was when he was at his peak (Napoleon's Hussars for example).
Einion