Ancient glass has been extensively studied from a technological and raw material provenance perspective since the middle of the 20th century. With the rising applications of analytical techniques in the field of Heritage Studies, the last two decades saw an exponential increase in publications on ancient and historical glass technology from around the globe. Given the amount of works on glass chemical composition, it is surprising to note that the long-held production model for Iron Age glasses found in Europe has only recently been challenged by the publication of uncharacteristic glass compositions. Traditionally, LBA glass industries based on plant-ash fluxes/HMG (Egypt and the Levant) and mixed-alkali fluxes/LMHK (Italy) are thought to be supplanted by natron-fluxed/LMG production operating in Egypt and the Levant since around the 9th century BCE. Recently, however, arguments have been put forth for a more diversified network of glassmaking traditions, including small-scale autonomous European workshops. This article reviews the current state of research into Iron Age (1st millennium BCE) glasses in Europe by examining the available published data on glass compositions to critically assess some practical and theoretical issues stemming from this heterogenous field of research. Key questions are addressed, and future lanes of research are proposed.