This chapter provides an overview of sound inventories and analysis of some segmental changes from Old English (OE) to Present-Day English (PDE). The topic selection is based on relevance to the PDE phonological structure and to the way specific processes are elucidated by current models of language change. The empirical data are treated in terms of the changes’ mechanism and causation in relation to phonetic and system-internal triggers, and in the context of language contacts and sociocultural pressures. Updating the results of existing accounts, the chapter includes many familiar processes, highlighting areas that are either missing or under-represented in the canon. The notorious letter-sound discrepancy for vowels in PDE is prioritised, while space limitations require a less nuanced survey and analysis of consonantal and prosodic changes.

Umlaut and ablaut as morphological (rather than phonological) processes, affix order and bracketing paradoxes, subcategorization and stratum ordering, critique of Optimality Theory with respect to its ability to account for major phonological patterns in English, as described in rule terms in the preceding chapters. These include stress, vowel shift, and laxing. Special attention is given to opacity. Opacity presents the same problem to Optimality Theory as it does to pre-Generative structuralist phonology, due to its output orientation. Velar Softening is opaque in medicate (underapplication) and in criticize (overapplication). Various patches proposed to deal with this issue have involved the reintroduction of the intermediate derivational stages that Optimality Theory was designed to eliminate. These patches do not allow for Duke of York derivations such as that which appears in English in the derivation of pressure. The device of stratal Optimality Theory, combining level ordering and constraints differently ranked on different strata, can account for some Duke of York derivations but at the expense of making some postlexical processes lexical.

The article examines the history of noun inflection from Proto-Germanic to the modern Germanic languages which simplified the former system to different degrees. Icelandic preserved the most complex structures whereas English lost declension classes as well as gender and case. Interestingly, languages with three genders use them for the organization of their noun inflection, whereas those with two genders tend to dissociate them from declension. Most languages formalized their plural expression, i.e., morphological, phonological, or prosodic features of the stem determine the plural allomorph. The article shows that German developed a rather complex noun class system, which is based on semantics, gender, and form. Zero inflection can only be found in languages with distinct singular and plural articles. If these articles are homophonous, overt plural inflection is obligatory. These interrelations show that the noun is integrated into the NP and that its components contribute to the expression of the nominal categories.