'Should a conditional marker arise' … The diachronic development of conditional 'sollte' in German

Like other Germanic languages, German has a modal verb that, when used in the protasis of a conditional, does not have one of the modal meanings it has in other contexts, but only seems to underline the conditional meaning. The current paper looks at the diachronic development of conditional 'sollen', and shows how the past (subjunctive) form 'sollte', particularly in V1-protases, is in the process of developing into a pure conditional marker. Following Breitbarth (2015) and Breitbarth et al. (2016), this development is analysed in a framework combining Roberts & Roussou’s (2003) Minimalist approach to grammaticalization with a cartographic analysis of modality and conditionals based on Cinque (1999) and Haegeman (2010b)