Irish whiskey was one of the earliest distilled drinks in Europe. It is believed that Irish monks brought the technique of distilling perfumes back to Ireland from their travels to the Mediterranean countries around 1000 A.D. The Irish then modified this technique to obtain a drinkable spirit.
Similar to Scotch, the whiskey should be aged in barrels for at least 3 years before it can be labelled Irish. Most Irish whiskey is distilled thrice, compared to Scotch whisky, which is usually distilled twice but that of course is not necessarily a rule.
An interesting fact is that the ‘e’ in the word whiskey is believed to have been added by the Irish in order to differentiate their spirit from the low quality Scotch produced in the 19th century and largely shipped to America.