We present a novel account of the development and loss of one type of V2 word order over the Middle and early Modern English periods, based on a fine-grained corpus study which shows that multiple factors are at play, in interaction between syntax, information structure and prosody. We focus on finite verb movement to the highest functional head in the C-domain (Force) of the main clause: subject-finite inversion with pronominal subjects following an initial adverb (þa, þonne) in Old English. Middle English first sees the extension of this V2-context to other initial short deictic adverbs: here, there, nu, yet and thus. The choice of verb is narrowed down to auxiliaries and monosyllabic lexical verbs. V2 following adverbs is subsequently lost over the early Modern period. We show that this loss coincides with the grammaticalization of modals and other auxiliaries, leading to the loss of primary stress on the auxiliary. This triggered metrical changes in the clause-initial prosodic word: as long as the unstressed initial adverb could co-occur with a stressed monosyllabic finite verb, and the post-verbal subject pronoun could be integrated into the prosodic word of the auxiliary, inversion flourished. The loss of primary stress on the auxiliary yielded an unheaded foot, violating prosodic requirements. Our multifactorial treatment
of the development and loss of V2 implies that the process we find is best treated in terms of micro-variation
