"The original old fashioned recipe would have showcased the whiskey available in America in the 19th century: Irish, Bourbon or rye whiskey.[15] But in some regions, especially Wisconsin, brandy is substituted for whiskey (sometimes called a brandy old fashioned).[16][17][18] Eventually the use of other spirits became common, such as a gin recipe becoming popularized in the late 1940s.[15]
https://en.wikipedia.org/wiki/Old_fashioned_(cocktail)#Modifications
-Paul
https://en.wikipedia.org/wiki/Old_fashioned_(cocktail)#Modifications
-Paul