When you are about to have sex with your girlfriend, when out of nowhere Clint Eastwood walks in and has his way with your chick. After he is done he gets up, dusts off his pants, and leaves while giving you a charming wink.
Irish history written from an Irish Republicanperspective, i.e. in the style of the Irish historian and journalist, Tim Pat Coogan.
Historians often write from a particular perspective ; Cooganism is Irish history written from an Irish Republicanperspective, as is typical of the writings of Tim Pat Coogan.