Phonological history of English

This section summarizes the changes occurring within distinct time periods, covering the last 2,000 years or so. Within each subsection, changes are in approximate chronological order.

The time periods for some of the early stages are quite short due to the extensive population movements occurring during the Migration Period (early AD), which resulted in rapid dialect fragmentation.

The following table shows a possible sequence of changes for some basic vocabulary items, leading from Proto-Indo-European (PIE) to Modern English. The notation ">!" indicates an unexpected change, whereas the simple notation ">" indicates an expected change. An empty cell means no change at the given stage for the given item. Only sound changes that had an effect on one or more of the vocabulary items are shown.

NOTE: Some of the changes listed above as "unexpected" are more predictable than others. For example:

This table omits the history of Middle English diphthongs; see that link for a table summarizing the developments.

This table only describes the changes in accented syllables. Vowel changes in unaccented syllables were very different and much more extensive. In general: