From the II to the I century BC, the Latin orthography underwent a notable process of standardization. Among the many other (at least attempted) orthographic ‘reforms’ a new spelling variant for the cluster /ks/ began to emerge. The use of <XS> alongside the conventional <X> became increasingly popular in inscriptions of the time. This spelling variant has been the subject of great interest among scholars, who have delved deep into its origins. In this article, we take a closer look at the inception of <XS> and its subsequent diffusion, examining it from both a socio-cultural and a linguistic perspective. We will propose that the diffusion stemmed from both phono-graphemic and morpho-graphemic factors, as well as the ever-more strong influence of Greek's spelling system on Latin.