One of the most salient markers of northern English pronunciation, and the only one which involves a difference between dialects of the North (and Midlands) and those of the South as far as their phonemic inventories are concerned, is the lack of what Wells (1982: 132) terms the “FOOT–STRUT split” everywhere in England north of Birmingham. This split is of relatively recent origin, and is the result of unrounding of the Middle English short  in certain environments. By the middle of the eighteenth century the ‘unsplit’  was already recognized as a northern characteristic. The Cumbrian John Kirkby remarked in 1746 that his “seventh vowel”, found in skull, gun, supper, figure, nature, “is scarce known to the Inhabitants of the North, who always use the short sound of the eighth vowel instead of it.” (quoted in Bergström 1955: 71) (Kirkby’s “eighth vowel” is long in too, woo, Food, etc., short in good, stood, Foot, etc. and so most likely to be  ~ /u:/) This suggests that 18th century northerners pronounced  where southerners had , but William Kenrick (1773: 36) indicates otherwise in his New Dictionary of the English Language.

It is further observable of this sound, that the people of Ireland, Yorkshire, and many other provincials mistake its use; applying it to words which in London are pronounced with the u full… as bull, wool, put, push, all of which they pronounce as the inhabitants of the Metropolis do trull, blood, rut, rush. Thus the ingenious Mr. Ward of Beverley, has given us in his grammar the words put, thus and rub as having one quality of sound.

Thus both Kirkby and Kenrick attest to the lack of any FOOT–STRUT split as a salient feature of northern speech in the 18^th century but whilst Kirkby suggests that the unsplit northern phoneme is , Kenrick’s account indicates that it is more like . In fact, both types of pronunciation exist in the North of England today. Wells (1982: 132) writes that “relatively open, STRUT– like qualities may be encountered as hypercorrections in FOOT words, as  ” whilst Watt and Milroy (1999: 28) note that in Newcastle “STRUT/FOOT may be heard as [ə], among middle-class speakers, particularly females.” Kenrick’s “Mr Ward of Beverly” could well have been describing a similarly hypercorrect or middle class pronunciation in his grammar. Quite apart from these hypercorrect pronunciations, realisations of the FOOT–STRUT vowel vary from  in the lower North and central Lancashire to something more like  in Tyneside and Northumberland.

Distribution of /u:/ and  across the FOOT and GOOSE sets also varies within and between northern dialects. Except in Tyneside and Northumberland, older speakers throughout the North have /u:/ in some FOOT words, notably cook, brook, hook. These words, along with such as stood, good, foot etc. would have had a long vowel until the 17^th century. 17^th century evidence shows that pronunciation of these words was very variable, with  and /u:/ all attested for the same words. In the case of words in which the vowel is followed by /k/, this shortening has simply taken much longer to affect certain northern dialects, but the short vowel is now spreading. There are also some words in which pronunciation varies idiosyncratically: in Tyneside, both  and /fu:d/ can be heard, but the distribution seems to be idiolectal rather than regional, and soot is likewise highly variable.