There's plenty of debate about the proper spelling of "whisky" (otherwise known as "whiskey") but there is a real, concrete answer: It depends on where the spirit comes from. In short, the spelling "whiskey" is common in the United States and Ireland. The rest of the world, including Japan, Scotland and Canada, uses "whisky."
The word originated from Gaelic for "water of life". "The Scots and Irish Gaelic translation of this is uisge beatha," says David Broom, author of The World Atlas of Whisky. "This referred to a proto-whisky redistilled with spices and herbs. The 'straight' version became known as 'usky'."
Whiskey has a long history in America. George Washington was persuaded by his Scottish plantation manager, James Anderson, to plant rye to make the popular spirit from Anderson’s homeland. The influx of Scotch and Irish immigrants in the 1800s helped create the American whiskey industry, and the brown liquor’s popularity in the States has grown by leaps and bounds since then, although with plenty of regional differences.
"American whiskey regulations have developed in an ad hoc manner," says Morgan. This is why, in the U.S., there are exceptions to the spelling of "whiskey." Most bourbon and Tennessee whiskies have the "e" except for a few rebels like George Dickel, Old Forester, and Maker's Mark. The Samuels family, distillers of Maker's Mark, have been distilling whisky for the past eight generations which is why they decided to pay homage to their Scottish ancestors by referring to the product they create as "whisky" instead of "whiskey."
Where the original variation in spelling came from is still a matter of debate. "Legend has it that during the 1800s, most Scotch Whisky was considered as very low quality," says Fletcher. Due to this, American and Irish distillers began adding the "e" in order to show a point of distinction to consumers that the quality of their whiskey was higher than that of Scotch. Today, it's little more than a regional tradition — one that causes its share of confusion.
"Whisky": Most of the world including Scotland, Japan, Canada, Australia, England, Finland, Germany and India
"Whiskey": Just the U.S. and Ireland.