Historical linguistics concerns itself with how the languages we speak today came to be the way they are. This text presents a collection of work done in historical linguistics from the perspective of Lexical-Functional Grammar (LFG), a lexical unification-based theory. The problems tackled are representitive of the field of historical linguistics in genreal, but the type of languages surveyed are varied. The book presents data from much studied languages like English and Italian, but also covers less well studied languages such as Pennsylvania Dutch, the South Asian language Urdu/Hindi and the Australian languages Waripri and Warumungu. The papers use LFG to examine morphosyntactic diatronic developments in a variety of typologically diverse languages. The topics covered include: the development or shift of case marking systems; the rise of auxilliaries; the origins of complex predication involving verb particles or light verbs; and the formation of complementizers.