Irish Mist was first produced at the Tullamore distillery in 1947 by D.E. Williams using a "heather wine" recipe that includes aged Irish whiskey, heather and clover honey, aromatic herbs, and other spirits. The liqueur was a success, but the company's whisky was less. In the end, they opted to close the distillery in 1954, renaming as the the Irish Mist Liqueur Co. When their warehoused stock began to run out, an agreement was reached with Powers in the 1960s, with the Dublin-distillers taking the Tullamore DEW brand in exchange for providing whiskey for the Irish Mist liqueur. 

This is a later example, produced using whiskey distilled by Irish Distillers (the amalgamation of Powers, Jameson and Cork Distillers) at Midleton, and bottled by the Irish Mist Liqueur Co under ownership by the C&C Group. They retained the brand until 2010 when they sold their entire spirits division, including Tullamore Dew (which they bought back from Irish Distillers in 1994), to William Grant & Sons.