The following study is an examination of the contribution of the Germanic place-names of southern Scotland to the onomasticon and lexicon of Britain generally and Scotland specifically. By building a corpus of the Germanic place-names so far identified in the south of Scotland, and interrogating this data in the light of recent onomastic scholarship, a wealth of material has been uncovered, which clearly establishes the importance of Scottish place-name data to the fields of British onomastics and historical lexicography. Over the last hundred years, English place-name scholars have demonstrated that English place-names are a valuable resource for evidence relating to early Germanic lexis in the British Isles. However, comparative material from Scotland has seldom been taken into account, and the present study aims to redress this imbalance by focusing primarily on Scottish data. The thesis is divided into two main sections, the first of which considers the contribution of Scottish place-names to the onomasticon by presenting an analysis of seventy-two elements that are not represented in the corpus of English place-names. The second section investigates place-name elements which are unattested in the literary corpus, and thus assesses the contribution of Scottish place-names to the lexicon. The definitions of many elements have been revised, and in some cases a consideration of the onomastic evidence has resulted in a reinterpretation of lexical usage. This thesis is also the first study to focus attention on qualifying elements rather than generics, and the first to collate the historical evidence for over five hundred Scottish place-name elements. As shown by this study, the Germanic toponymicon of southern Scotland deserves to take its place amongst the national resources for Scottish onomastics and historical lexicography.