While Present-Day English has SVO as its canonical word order, word order preferences have undergone substantial changes since Old English times. Not only has word order become more fixed (especially with respect to unmarked sentence-initial elements) in main clauses, but verb-final in subordinate clauses has also been lost. The change from V2 to SVO, in particular, has traditionally been attributed to changes in morphology (particularly the loss of case marking). As word order flexibility in declarative main clauses became more restricted, English developed alternative ways to reorder clause elements for information-structuring purposes, including different kinds of passive construction. This chapter reviews previous research on word order changes in the history of English with a view to showing major developments in the field of English historical syntax, such as the shift from largely qualitative to more quantitative, data-based approaches, a change in focus from canonical to non-canonical word order or from core to more peripheral clause elements. Major theoretical models serve as the backdrop of these developments in the field of English historical syntax.