Sarah Bond has put together a couple of interesting items and shared them via Twitter … click on the images to get a clearer look at the causes of death:
Pie Charting Imperial Demises
quidquid bene dictum est ab ullo, meum est
rogueclassicism 
The colors are hard to tell apart, on your top chart. It is too bad you did not use crosshatching or something to help differentiate some of the very similar greens or blues, etc. Could you not label the pie slices as so: (A) 2% (B) 5% … and then in your legend do this (A) [color] 2%, (B) [color] 5% ? It would make the data much easier to follow. Other than that, a masterful piece of work. A labour of love!
Your second chart is much more clear. But again, you could show the various groupings, which would reveal a wealth of information….
But as you commented: Daggers be Dangerous!
As a fan of Rome, you may like these two videos:
Julius Caesar (“Besame Mucho” by the Beatles)
Viva Roma No. V (“Mambo #5” by Lou Bega)