There are multiple artists with this name: 1) Union Jack are Simon Berry and Claudio Giussani, a trance music project from England. Best know for releasing the classic trance album "There Will Be No Armageddon". Founded in 1993, the duo has focused on acid and tech trance and has been closely associated with the Platipus record label. Their singles "Two Full Moons and a Trout" and "Red Herring" saw much club play in the early nineties." 2) Union Jack is a French ska-punk band. There are five members in this band: "XXX" on guitar and vocals, "Rude Ben" on bass and vocals, "Skrack" on drums and vocals, "Mr No" on saxophone, and "Low Cut" on Scratch. Though they are French, most of their lyrics are English. 3) Union Jack were a duo from Novi Sad (former Yugoslavia). They have released two tracks, for the then local CyberfArts DIY label. Listen here: Missed Calls