so, i'm a member of a non-religious celtic group - we're a social group of celtic origins basically - and i've been asked to do a presentation on celtic paganism, how it effected Scotland (specifically) up until modern day. i'm looking to give just a QUICK run-down of history. but i want to know that i have all of the research material i can get, so that i have the most-rounded presentiation.

obviously i have books on celtic paganism, since that's what i practice, but i want to go more historical and less magic centered.

can any of you lovelys help me out with book reccomendations?