This book examines the relationship between political identity and variation from a diachronic perspective, and how vernacular features could index political and ideological affiliations. Specifically, it explores the use of written Scots in the correspondence of Scottish politicians active during the Union of the Parliaments debates at the turn of the eighteenth century. Drawing from the frameworks of First, Second and Third Wave perspectives on variation, and combining macro-social statistical modelling with microsocial analysis, broad socio-political factors are empirically investigated...