Were the Dark Ages really dark? And were the Irish a shining light in the darkness?

Are the Irish and Scots Gaelic or Celtic? The Scots speak Scots Gaelic. Do the Irish speak Gaelic too? And how the heck do the Galls fit in?

From whiskey to ATMs, the Celts have made the world a better place. Here’s just a first list of the gifts they’ve given humankind.