|Browne Bushell being executed after betraying Scarborough Castle to the Royalists in March 1643.|
The cover of the September 2012 issue of History Today features an image of Charles I and Cromwell with the title 'Whose side are you on? Civil War Turncoats'. The start of the cover story can be read here.
You can watch a lecture by Dr Andrew Hopper - the article's author - on the same subject here. Dr Hopper was also kind enough to answer a few of my own questions prior to the recent Fairfax 400th Anniversary Conference about the Parliamentarian leader and the Siege of Colchester - the brief Q&A can be read here.