This is an article on the MacCarthy clan or sept during the Nine Years War of 1595-1603.
http://www.theirishstory.com/2011/04/13 ... 1595-1603/
Basically it argues that the unstable and splintered nature of Gaelic lordships made political unity among them impossible. As far as military aspects go, it shows that both sides, but especially the English, systematically practiced scorched earth warfare and targeted civilians at random.
