Proto-Celtic language
The Proto-Celtic language, also called Common Celtic, is the partially reconstructed proto-language of all the known Celtic languages. Its lexis, or vocabulary, can be confidently reconstructed on the basis of the comparative method of historical linguistics, in the same manner as Proto-Indo-European, the proto-language which has been most thoroughly reconstructed. Proto-Celtic is a descendant of the Proto-Indo-European language and is itself the ancestor of the Celtic languages which are members of the modern Indo-European language family, the most commonly spoken language family. Modern Celtic languages share common features with Italic languages that are unseen in other branches and according to one theory they may have formed an ancient Italo-Celtic branch. The duration of the cultures speaking Proto-Celtic was relatively brief compared to PIE's 2,000 years. The earliest archaeological culture that may justifiably be considered as Proto-Celtic is the Late Bronze Age Urnfield culture of Central Europe c.1300 BCE. By the Iron Age Hallstatt culture of around 800 BC these people had become fully Celtic.
The reconstruction of Proto-Celtic is currently being undertaken, by necessity relying on later iterations of Celtic languages. Although Continental Celtic presents much substantiation for Proto-Celtic phonology, and some for its morphology, recorded material is too scanty to allow a secure reconstruction of syntax, although some complete sentences are recorded in the Continental Gaulish and Celtiberian. Therefore, the primary sources for reconstruction come from the Insular Celtic languages with the oldest literature found in Old Irish and Middle Welsh, dating back to authors flourishing in the 6th century CE.
Sound changes from Proto-Indo-European
The phonological changes from Proto-Indo-European to Proto-Celtic may be summarised as follows. The changes are roughly in chronological order, with changes that operate on the outcome of earlier ones appearing later in the list.Late Proto-Indo-European
These changes were shared by several other Indo-European branches.- *e is colored by an adjacent laryngeal consonant:
- * eh₂, h₂e > ah₂, h₂a
- * eh₃, h₃e > oh₃, h₃o
- Palatovelars merge into the plain velars:
- * ḱ > k
- * ǵ > g
- * ǵʰ > gʰ
- Epenthetic *a is inserted after a syllabic sonorant if a laryngeal and another sonorant follow
- Laryngeals are lost:
- * before a following vowel
- * following a vowel in syllables before the accent
- * following a vowel, resulting in compensatory lengthening, thus
- * between plosives in non-initial syllables
- Two adjacent dentals become two adjacent sibilants
Italo-Celtic
- Dybo's rule: long close vowels are shortened before resonant + stressed vowel.
- * īR´ / ? *iHR´ > iR´
- * ūR´ / ? *uHR´ > uR´
- Possibly, post-consonantal laryngeals are lost when before pre-tonic close vowels:
- * CHiC´ > CiC´
- * CHuC´ > CuC´
- Development of initial stress, following the previous two changes.
- Possibly, vocalization of laryngeals to *ī between a *CR cluster and consonantal *j
- Syllabic laryngeals become *a
- Syllabic resonants before a voiced unaspirated stop become *Ra
- *m is assimilated or lost before a glide:
- * mj > nj
- * mw > w
- *p assimilates to *kʷ when another *kʷ follows later in the word
- sVs > ss, sTVs > Ts
- Word-initially, HR̥C > aRC
- Before voiceless stops, CR̥HT > CRaT
- CR̥HV > CaRHV
- CR̥HC > CRāC
Early Proto-Celtic
- Sequences of velar and *w merge into the labiovelars :
- * kw > kʷ
- * gw > gʷ
- * gʰw > gʷʰ
- gʷ > b
- Aspirated stops lose their aspiration and merge with the voiced stops :
- * bʰ > b
- * dʰ > d
- * gʰ > g
- * gʷʰ > gʷ
- *e before a resonant and *a becomes *a as well : *ǵʰelH-ro > *gelaro > *galaro / *gérH-no > *gerano > *garano.
- Epenthetic *i is inserted after syllabic liquids when followed by a plosive:
- * l̥T > liT
- * r̥T > riT
- Epenthetic *a is inserted before the remaining syllabic resonants:
- * m̥ > am
- * n̥ > an
- * l̥ > al
- * r̥ > ar
- All remaining nonsyllabic laryngeals are lost.
- ē > ī
- ō > ū in final syllables
- Long vowels are shortened before a syllable-final resonant ; this also shortens long diphthongs.
Late Proto-Celtic
- Plosives become *x before a different plosive or *s
- p > b before liquids
- p > w before nasals
- p > ɸ
- ō > ā
- ew > ow
- uwa > owa
Examples
Phonological reconstruction
Consonants
The following consonants have been reconstructed for Proto-Celtic:In contrast to the parent language, Proto-Celtic does not use aspiration as a feature for distinguishing phonemes. So the Proto-Indo-European voiced aspirated stops *, *, * merged with *, *, *. The voiced aspirate labiovelar * did not merge with *, though: plain * became * in Proto-Celtic, while aspirated * became *. Thus, PIE * 'woman' became Old Irish ben and Old Welsh ben, but PIE * 'to kill, to wound' became Old Irish gonaid and Welsh gwanu.
Proto-Indo-European * was lost in Proto-Celtic, apparently going through the stages * and * before being lost completely word-initially and between vowels. Adjacent to consonants, Proto-Celtic * underwent different changes: the clusters * and * became * and * respectively already in Proto-Celtic. PIE * became Old Irish s and Brythonic f; while argues there was an intermediate stage *, finds it more economical to believe that * remained unchanged in PC, that is, the change * to * did not happen when * preceded.
| Proto-Celtic | Old Irish | Welsh |
| * > * 'shine' | las-aid | llach-ar |
| * > * 'seven' | secht | saith |
| * or * 'heel' | seir | ffêr |
In Gaulish and the Brittonic languages, a new * sound has arisen as a reflex of the Proto-Indo-European * phoneme. Consequently, one finds Gaulish petuar, Welsh pedwar "four", compared to Old Irish cethair and Latin quattuor. Insofar as this new fills the space in the phoneme inventory which was lost by the disappearance of the equivalent stop in PIE, we may think of this as a chain shift.
The terms P-Celtic and Q-Celtic are useful when we wish to group the Celtic languages according to the way they handle this one phoneme. However a simple division into P- and Q-Celtic may be untenable, as it does not do justice to the evidence of the ancient Continental Celtic languages. The large number of unusual shared innovations among the Insular Celtic languages are often also presented as evidence against a P-Celtic vs Q-Celtic division, but they may instead reflect a common substratum influence from the pre-Celtic languages of Britain and Ireland,, or simply continuing contact between the insular languages; in either case they would be irrelevant to Celtic language classification in the genetic sense.
Q-Celtic languages may also have in loan words, though in early borrowings from Welsh into Primitive Irish was used by sound substitution due to a lack of a phoneme at the time:
- Latin Patricius "Saint Patrick"' > Welsh > Primitive Irish > Old Irish Cothrige, later Pádraig;
- Latin presbyter "priest" > early form of word seen in Old Welsh premter primter > Primitive Irish > Old Irish cruimther.
Vowels
The Proto-Celtic vowel system is highly comparable to that reconstructed for Proto-Indo-European by Antoine Meillet. The following monophthongs have been reconstructed:The following diphthongs have also been reconstructed:
| Type | With -i | With -u |
| With e- | ||
| With a- | ||
| With o- |
Morphology
Nouns
The morphology of nouns and adjectives demonstrates no arresting alterations from the parent language. Proto-Celtic is believed to have had nouns in three genders, three numbers and five to eight cases. The genders were the normal masculine, feminine and neuter, the three numbers were singular, plural and dual. The number of cases is a subject of contention: while Old Irish may have only five, the evidence from Continental Celtic is considered rather unambiguous despite appeals to archaic retentions or morphological leveling. These cases were nominative, vocative, accusative, dative, genitive, ablative, locative and instrumental.Nouns fall into nine or so declensions, depending on the stem. There are *o-stems, *ā-stems, *i-stems, *u-stems, dental stems, velar stems, nasal stems, *r-stems and *s-stems.
*''o''-stem nouns
- makkʷos 'son'
| Case | Singular | Dual | Plural |
| Nominative | *makkʷos | *makkʷou | *makkʷoi |
| Vocative | *makkʷe | *makkʷou | *makkʷūs |
| Accusative | *makkʷom | *makkʷou | *makkʷūs |
| Genitive | *makkʷī | *makkʷūs | *makkʷom |
| Dative | *makkʷūi | *makkʷobom | *makkʷobos |
| Ablative | *makkʷū | *makkʷobim | *makkʷobis |
| Instrumental | *makkʷū | *makkʷobim | *makkʷūs |
| Locative | *makkʷei | *makkʷou | *makkʷobis |
- dūnom 'stronghold'
| Case | Singular | Dual | Plural |
| Nominative | *dūnom | *dūnou | *dūnā |
| Vocative | *dūnom | *dūnou | *dūnā |
| Accusative | *dūnom | *dūnou | *dūnā |
| Genitive | *dūnī | *dūnūs | *dūnom |
| Dative | *dūnūi | *dūnobom | *dūnobos |
| Ablative | *dūnū | *dūnobim | *dūnobis |
| Instrumental | *dūnū | *dūnobim | *dūnūs |
| Locative | *dūnei | *dūnou | *dūnobis |
*''ā''-stem nouns
E.g. *ɸlāmā 'hand'| Case | Singular | Dual | Plural |
| Nominative | *ɸlāmā | *ɸlāmai | *ɸlāmās |
| Vocative | *ɸlāmā | *ɸlāmai | *ɸlāmās |
| Accusative | *ɸlāmām | *ɸlāmai | *ɸlāmās |
| Genitive | *ɸlāmās | *ɸlāmajous | *ɸlāmom |
| Dative | *ɸlāmāi | *ɸlāmābom | *ɸlāmābos |
| Ablative | *ɸlāmī | *ɸlāmābim | *ɸlāmābis |
| Instrumental | *ɸlāmī | *ɸlāmābim | *ɸlāmābis |
| Locative | *ɸlāmāi | *ɸlāmābim | *ɸlāmābis |
E.g. *wolkās 'hawker'
| Case | Singular | Dual | Plural |
| Nominative | *wolkās | *wolkai | *wolkās |
| Vocative | *wolkā | *wolkai | *wolkās |
| Accusative | *wolkām | *wolkai | *wolkās |
| Genitive | *wolkās | *wolkajous | *wolkom |
| Dative | *wolkāi | *wolkābom | *wolkābos |
| Ablative | *wolkī | *wolkābim | *wolkābis |
| Instrumental | *wolkī | *wolkābim | *wolkābis |
| Locative | *wolkāi | *wolkābim | *wolkābis |
*''i''-stems
E.g. *sūlis 'sight, view, eye'| Case | Singular | Dual | Plural |
| Nominative | *sūlis | *sūlī | *sūlīs |
| Vocative | *sūli | *sūlī | *sūlīs |
| Accusative | *sūlim | *sūlī | *sūlīs |
| Genitive | *sūleis | *sūljous | *sūljom |
| Dative | *sūlei | *sūlibom | *sūlibos |
| Ablative | *sūlī | *sūlibim | *sūlibis |
| Instrumental | *sūlī | *sūlibim | *sūlibis |
| Locative | *sūlī | *sūlibim | *sūlibis |
E.g. *mori 'body of water, sea'
| Case | Singular | Dual | Plural |
| Nominative | *mori | *morī | *morjā |
| Vocative | *mori | *morī | *morjā |
| Accusative | *mori | *morī | *morjā |
| Genitive | *moreis | *morjous | *morjom |
| Dative | *morei | *moribom | *moribos |
| Ablative | *morī | *moribim | *moribis |
| Instrumental | *morī | *moribim | *moribis |
| Locative | *morī | *moribim | *moribis |
*''u''-stem nouns
E.g. *bitus 'world, existence'| Case | Singular | Dual | Plural |
| Nominative | *bitus | *bitou | *bitowes |
| Vocative | *bitu | *bitou | *bitowes |
| Accusative | *bitum | *bitou | *bitūs |
| Genitive | *bitous | *bitowou | *bitowom |
| Dative | *bitou | *bitubom | *bitubos |
| Ablative | *bitū | *bitubim | *bitubis |
| Instrumental | *bitū | *bitubim | *bitubis |
| Locative | *bitū | *bitubim | *bitubis |
E.g. *dānu 'valley river'
| Case | Singular | Dual | Plural |
| Nominative | *dānu | *dānou | *dānwā |
| Vocative | *dānu | *dānou | *dānwā |
| Accusative | *dānu | *dānou | *dānwā |
| Genitive | *dānous | *dānowou | *dānowom |
| Dative | *dānou | *dānubom | *dānubos |
| Ablative | *dānū | *dānubim | *dānubis |
| Instrumental | *dānū | *dānubim | *dānubis |
| Locative | *dānū | *dānubim | *dānubis |
Velar and dental stems
Before the *-s of the nominative singular, a velar consonant was fricated to *-x : *rīg- "king" > *rīxs. Likewise, final *-d devoiced to *-t-: *druwid- "druid" > *druwits.E.g. *rīxs 'king'
| Case | Singular | Dual | Plural |
| Nominative | *rīxs | *rīge | *rīges |
| Vocative | *rīxs | *rīge | *rīges |
| Accusative | *rīgam | *rīge | *rīgās |
| Genitive | *rīgos | *rīgou | *rīgom |
| Dative | *rīgei | *rīgobom | *rīgobos |
| Ablative | *rīgī | *rīgobim | *rīgobis |
| Instrumental | *rīge | *rīgobim | *rīgobis |
| Locative | *rīgi | *rīgobim | *rīgobis |
E.g. *druwits 'druid'
| Case | Singular | Dual | Plural |
| Nominative | *druwits | *druwide | *druwides |
| Vocative | *druwits | *druwide | *druwides |
| Accusative | *druwidem | *druwide | *druwidās |
| Genitive | *druwidos | *druwidou | *druwidom |
| Dative | *druwidei | *druwidobom | *druwidobos |
| Ablative | *druwidī | *druwidobim | *druwidobis |
| Instrumental | *druwide | *druwidobim | *druwidobis |
| Locative | *druwidi | *druwidobim | *druwidobis |
E.g. *karnuxs 'carnyx'
| Case | Singular | Dual | Plural |
| Nominative | *karnuxs | *karnuke | *karnukes |
| Vocative | *karnuxs | *karnuke | *karnukes |
| Accusative | *karnukam | *karnuke | *karnukās |
| Genitive | *karnukos | *karnukou | *karnukom |
| Dative | *karnukei | *karnukobom | *karnukobos |
| Ablative | *karnukī | *karnukobim | *karnukobis |
| Instrumental | *karnuke | *karnukobim | *karnukobis |
| Locative | *karnuki | *karnukobim | *karnukobis |
E.g. *karants 'friend'
| Case | Singular | Dual | Plural |
| Nominative | *karants | *karante | *karantes |
| Vocative | *karants | *karante | *karantes |
| Accusative | *karantam | *karante | *karantās |
| Genitive | *karantos | *karantou | *karantom |
| Dative | *karantei | *karantobom | *karantobos |
| Ablative | *karantī | *karantobim | *karantobis |
| Instrumental | *karante | *karantobim | *karantobis |
| Locative | *karanti | *karantobim | *karantobis |
Nasal stems
Generally, nasal stems end in *-on-; this becomes *-ū in the nominative singular: *abon- "river" > *abū.E.g. *abū 'river'
| Case | Singular | Dual | Plural |
| Nominative | *abū | *abone | *abones |
| Vocative | *abū | *abone | *abones |
| Accusative | *abonam | *abone | *abonās |
| Genitive | *abonos | *abonou | *abonom |
| Dative | *abonei | *abnobom | *abnobos |
| Ablative | *abonī | *abnobim | *abnobis |
| Instrumental | *abone | *abnobim | *abnobis |
| Locative | *aboni | *abnobim | *abnobis |
E.g. *anman 'name'
| Case | Singular | Dual | Plural |
| Nominative | *anman | *anmane | *anmanes |
| Vocative | *anman | *anmane | *anmanes |
| Accusative | *anmanam | *anmane | *anmanās |
| Genitive | *anmanos | *anmanou | *anmanom |
| Dative | *anmanei | *anmanobom | *anmanobos |
| Ablative | *anmanī | *anmanobim | *anmanobis |
| Instrumental | *anmane | *anmanobim | *anmanobis |
| Locative | *anmani | *anmanobim | *anmanobis |
*''s''-stem nouns
Generally, *s-stems end in *-es-, which becomes *-os in the nominative singular: *teges- 'house' > *tegos.E.g. *tegos 'house', Old Irish teg, tech, dative tigh; Welsh tŷ, Breton ti.
| Case | Singular | Dual | Plural |
| Nominative | *tegos | *tegese | *tegeses |
| Vocative | *tegos | *tegese | *tegeses |
| Accusative | *tegesam | *tegese | *tegesās |
| Genitive | *tegesos | *tegesou | *tegesom |
| Dative | *tegesei | *tegesobom | *tegesobos |
| Ablative | *tegesī | *tegesobim | *tegesobis |
| Instrumental | *tegese | *tegesobim | *tegesobis |
| Locative | *tegesi | *tegesobim | *tegesobis |
*''r''-stem nouns
- r-stems are rare and principally confined to names of relatives. Typically they end in *-ter-, which becomes *-tīr in the nominative and *-tr- in all other cases aside from the accusative: *ɸater- 'father' > *ɸatīr, *ɸatros.
| Case | Singular | Dual | Plural |
| Nominative | *ɸatīr | *ɸatere | *ɸateres |
| Vocative | *ɸatīr | *ɸatere | *ɸateres |
| Accusative | *ɸateram | *ɸatere | *ɸaterās |
| Genitive | *ɸatros | *ɸatrou | *ɸatrom |
| Dative | *ɸatrei | *ɸatrebom | *ɸatrebos |
| Ablative | *ɸatrī | *ɸatrebim | *ɸatrebis |
| Instrumental | *ɸatre | *ɸatrebim | *ɸatrebis |
| Locative | *ɸatri | *ɸatrebim | *ɸatrebis |
E.g. *mātīr 'mother'
| Case | Singular | Dual | Plural |
| Nominative | *mātīr | *mātere | *māteres |
| Vocative | *mātīr | *mātere | *māteres |
| Accusative | *māteram | *mātere | *māterās |
| Genitive | *mātros | *mātrou | *mātrom |
| Dative | *mātrei | *mātrebom | *mātrebos |
| Ablative | *mātrī | *mātrebim | *mātrebis |
| Instrumental | *mātre | *mātrebim | *mātrebis |
| Locative | *mātri | *mātrebim | *mātrebis |
Verbs
From comparison between early Old Irish and Gaulish forms it seems that Continental and Insular Celtic verbs were to develop differently and so the study of Irish and Welsh may have unduly weighted past opinion of proto-Celtic verbal morphology. It can be inferred from Gaulish and Celtiberian as well as Insular Celtic that the proto-Celtic verb had at least three moods:- indicative — seen in e.g. 1st sg. Gaulish delgu "I hold", Old Irish tongu "I swear"
- imperative — seen in e.g. 3rd sg. Celtiberian usabituz, Gaulish appisetu
- subjunctive — seen in e.g. 3rd sg. Gaulish buetid "may he be", Celtiberian asekati
- present — seen in e.g. Gaulish uediíu-mi "I pray", Celtiberian zizonti "they sow"
- preterite — seen in e.g. 3rd sg. Gaulish sioxti, Lepontic KariTe
- imperfect — perhaps in Celtiberian kombalkez, atibion
- future — seen in e.g. 3rd sg. Gaulish bissiet, Old Irish bieid "he shall be"
Verbs were formed by adding suffixes to a verbal stem. The stem might be thematic or athematic, an open or a closed syllable.
;Example conjugations
Scholarly reconstructions may be summarised in tabular format.
;Conjugation like *bere/o- 'bear, carry, flow'
;Conjugation like *mārā- 'greaten, magnify, enlarge'