This article sets out to clarify the contribution of syntactic properties and subject weight for variation between verb-subject and subject-verb order in a database of fourteenthand fifteenth-century prose. It sets out the syntactic structures which are assumed, and investigates the impact on ordering of a set of factors, using established quantitative methodologies. A series of conclusions includes the continuing distinct status of initial then, the systematic importance of clause-final position, the different impacts of subject length in different contexts, and the presence of a definiteness effect for the late placement of a subject after a nonfinite unaccusative. 1 I am delighted to acknowledge a research readership granted by the British Academy which gave me the time to collect the data investigated here, and the comments of audiences atIn today's English the choice of order in such clause types seems to involve both syntactic and other factors. The reversed order is clearly required with BE when its predicate is fronted as in (1a), and it is promoted by the presence of an unaccusative verb as in (1b-d). It has also been suggested that it involves the structuring of information. Birner (1994: 233) claimed that the ordering of examples like (1) above in a present-day corpus 'depends on the relative discourse-familiarity of the information represented by the preposed and postposed constituents', so that information that is more familiar precedes information that is less familiar, in line with the general view (variously defined, and expressed in different terms by different theorists) that 'given' information precedes 'new' information. But it may not only be the relative information status of constituents that is involved here. Wasow (2002) discusses factors which are relevant to the choice of a particular order of postverbal constituents in several constructions in Present-day English where variation in order is found. He notes that the comparative grammatical weight of a constituent (potentially defined in terms of its length or its grammatical complexity) plays a major role, with a strong tendency for less weighty constituents to precede more weighty constituents, and he goes on to suggest that utterance planning may be a crucial factor underlying this tendency. He also presents evidence that in at least some constructions weight and information structuring are distinct parameters, though in general their contribution is difficult to distinguish (2002: 69-81). Both of course are likely to reflect the planning and production, and the parsing and perception of utterances. Wasow notes more generally that the question of what factors motivate the selection of a particular order is a complex one with 'no simple answer ' (2002: 109). See Culicover & Levine (2001) for some further recent discussion and analysis of inversion in Present-day English, Green (1980) and Stockwell (1984) for earlier discussion.It is clear that information structuring and grammatical weight also had considerable importance in earlier E...