Old Nubian is a Nilo-Saharan language (Greenberg 1963: 85, 130) spoken in the medieval Nubian kingdoms established above the First Cataract of the Nile: Nobadia, Makuria, and Alwa.1 It has been attested between the 8th and 15th centuries (Browne 2002: 1), with a highpoint around the 12th century (Ochała 2014: 41–42). The kingdoms were Christian, and the attested textual material that remains comprises both literary and documentary texts.

Old Nubian is part of the Nubian family within the North-Eastern Sudanic subgroup of the Nilo-Saharan phylum. Its closest relatives are the Nile Nubian languages Andaandi (Dongolawi), Mattokki (Kenzi), and Nobiin, as well as the Western Nubian languages that include Birgid, Midob, and a diverse group of Kordofan Nubian languages. Together with Meroitic, it is the oldest known representative of the Nilo-Saharan phylum, the least studied of all African macro-families.

Old Nubian is an agglutinative SOV language (Browne 2002: 91), with a nominative–accusative case marking system (van Gerven Oei 2014: 170–74).

Although perhaps obvious, it should be pointed out that Old Nubian is a dead language. This means that our data set is by definition limited to the Old Nubian texts that have been published and those that we still hope to find at archeological excavations. In spite of this considerable handicap, we hope to prove that the set of “personal endings” thus far quietly assumed to be agreement morphemes are in fact a set of subject clitics.

Old Nubian features a series of morphemes that appear on verbal forms after tense morphology, but before the predicate marker -ⲁ -a (Table 1).2 These morphemes are referred to in the literature as “personal endings” (Browne 2002: 49; Bechhaus-Gerst 2011: 72; Smagina 2017: 38).

These morphemes are not always present on verbal forms, thus leading scholars to differentiate between “non-finite” or “predicative” forms, which don’t exhibit these morphemes (Hintze 1971: 287; Browne 2002: 50; Bechhaus-Gerst 2011: 68), and “finite” or “indicative” forms, which do (Hintze 1977: 39; Browne 2002: 50; Bechhaus-Gerst 2011: 71). The prevalence of this terminology tacitly suggests that the “personal endings” should be interpreted as agreement morphology.

I have argued, however, that the finiteness of a verb should not be correlated with the presence of one of these cross-referencing morphemes, but rather with the presence of predicate marker -a (van Gerven Oei 2015a: 317–322).3 Thus, an explanation for the distribution of these “personal endings” should be sought elsewhere.

In order to determine the morphological and syntactical status of this set of morphemes, let us first investigate their precise distribution.

First, they are usually absent when the subject of the sentence is overt, unless it is marked by the topic marker -ⲉⲓⲟⲛ -eion.4 Compare the following two phrases from a text known as The Miracle of Saint Mēnas:5

Apart from the difference in preterite marker, which we will not address here,6 the verbal forms in examples (1) and (2) differ in that the latter features a personal ending, whereas the former doesn’t. In his analysis of this text, Browne (1994: 32) suggests this variation may be “because of similar variation in the Greek Vorlage,” where pesara ‘say-PST1-PRED’ would correspond to the Greek present tense legei and pessna ‘say-PST2-2/3SG-PRED’ to Greek aorist eipen. Evidence from bilingual psalms, however, shows that this matching is not consistent throughout Nubian translations from Greek and should therefore be discarded. I will argue below that the decisive difference between (1) and (2) is the presence of the topic marker -eion in (2), which shows that the subject has moved leftward out of its original position.

Second, “personal endings” are usually present when the subject is null.

In (3), the first person singular subject is not overtly expressed. Instead we find a personal ending on the main verb teeil douddre ‘hope exist-INTEN-PRS-1SG.PRED.’7

These preliminary data show that an interpretation of the Old Nubian “personal endings” as agreement morphology is questionable.

Fuß (2005: 130–39) provides a typological framework that allows us to interpret the data on Old Nubian “personal endings” presented above, offering several syntactic and morphological criteria (based on Zwicky & Pullum 1983)11 to distinguish clitics from agreement markers. Not all syntactic and morphological criteria listed by Fuß are applicable or testable in Old Nubian, for lack of living speakers. I have only listed those that can be verified based on the extant material. Moreover, because agreement is completely absent in Old Nubian, it is difficult to test the morphological criteria language-internally. Comparative evidence with Nobiin and Mattokki, however, gives us some indication of their validity.

Old Nubian exhibits effects of what Siewierska (2004: 159) calls “focus hierarchy,” the restriction of cross-referencing to non-focus-marked constituents. She provides several examples, including from the Chalcatongo Mixtec language (Macaulay 1996). Chalcatongo Mixtec is an VSO language, where a focus-marked subject precedes the verb. Topics move even further to the left.

(30) shows a full subject DP in preverbal focus position and a verb without subject clitic. In (31), the subject is the topic of the sentence, and therefore a subject clitic is allowed.

We find a similar distribution in Old Nubian. Although clitic doubling has been attested with definite DPs, it is absent when the DP in question is marked with the focus marker -ⲗⲟ/-ⲗⲱ -lo/-lō.12

In the first clause of (32), the subject sallō ‘word-FOC’ is marked with the focus marker -lō, while the main verb douara ‘exist-PST1-PRED’ remains without subject clitic. In the second clause, sallon has become the topic, leaving a subject gap, while the focus has shifted to tillilalo ‘God-DAT-FOC.’ As a result, we find a subject clitic on douona ‘exist-PST1-2/3SG-PRED.’ This example shows clearly how topic and focus marking and subject clitics interact.

In general, it appears that the presence of the focus marker -lo is correlated with the absence of movement:

Thus the behavior of the Old Nubian focus marker complements our other data. Focus-marked subjects do not move leftward and are therefore correlated with the absence of subject clitics on the verb.

Fuß (2005: 2) remarks that “it is a long-standing observation in historical linguistics that verbal agreement morphology develops from (originally independent) personal pronouns” and that clitics play a key role in the transition from pronoun to regular agreement. Based on previous literature he proposes the following grammaticalization scheme:

In the case of Old Nubian subject clitics, it appears that it is possible to establish a historical relation between pronouns and subject clitics:

The different origins of first/second person and third person clitics, personal and demonstrative pronouns respectively, is not uncommon. Oswald Szemerényi argues that Proto-Indo-European person suffixes developed along the same lines (see Fuß 2005: 18n4). It is unclear at which stage in the history of Old Nubian the development from weak pronoun to clitic pronoun took place, but it appears that the incorporation of pronominal elements in the verbal complex was not restricted to cross-referencing with the subject. For example, Smagina (2017: §46) argues that the passive marker -tak, derives from an incorporated 3SG.ACC pronoun tak(ka).

The impetus for the reinterpretation of these subject clitics as agreement morphology in the Nile Nubian languages Nobiin and the closely related language varieties Mattokki (Kenzi) and Andaandi (Dongolawi) may have very well been the clitic doubling constructions with specific DPs discussed above. In Nobiin, the subject clitics have fused with tense morphology, and have become a stable agreement paradigm that is obligatory for any main verb (Bechhaus-Gerst 2011: 75–84).14 Mattokki, on the other hand, seems to have preserved the Old Nubian system, with only little change (Table 2).15

Fuß (2005: 233) claims that “[n]ew verbal agreement morphology arises only for those slots of the agreement paradigm where the existing verbal inflection is non-distinctive.” The data from Nobiin confirm this. Whereas the Old Nubian subject clitic paradigm had several syncretic forms (2/3SG and 1/2PL), Nobiin features innovative 2SG and 2PL forms. As may be observed in Table 2, the 2SG and 2PL agreement suffixes differ considerably from the Old Nubian tense + subject clitics, creating new, distinctive forms. The -k in the 2PL form can be traced back to the Old Nubian 2PL clitic -ⲕⲉ -ke (see (29)).16

Although the appearance of the clitic -ke is uncommon in Old Nubian texts, its nascent development should most probably be correlated with the grammaticalization process described above, with its usage in Nobiin becoming generalized up to the point that it became part of the 2PL agreement suffix. As for the second part of the innovative Nobiin agreement suffixes, -(a)m, we see a reflex of the Old Nubian finite predicate marker -a and the affirmative marker -ⲙ(ⲁ) -m(a).

Again this morpheme rarely appears in Old Nubian in this form, but as is clear from (25), it appears in contexts where disambiguation may have been necessary, which led to a grammaticalization of the form in both 2SG and 2PL agreement markers in Nobiin.17 We may therefore posit the following historical development:

As is clear from Table 2, Mattokki appears to be more conservative than Nobiin in its preservation of the neutral tense paradigm. The same appears to be true of the past tense, where Mattokki shows a preservation of the -s from the Old Nubian second preterite, whereas Nobiin has a syncretic paradigm combining forms from the Old Nubian first and second preterite (Bechhaus-Gerst 2011: 82–83).18

The development of agreement in contemporary Nile Nubian languages has led to the complete collapse of the Old Nubian discourse marking morphology. Both the topic marker -eion and focus marker -lo have disappeared without any trace. Considering the interaction and interdependence of topic and focus marking and the series of subject clitics that we described above, this may perhaps not be surprising, but begs the question about how the distribution of these morphemes in Old Nubian, and their eventual disappearance, can be modeled. Fuß’s approach only allows us to explain the development from subject clitic to agreement, but lacks an explanation for the larger collapse of the Old Nubian discourse marking system.

At the same time, it appears that Nobiin and Andaandi/Mattokki have developed a new series of clitics based on several Old Nubian auxiliary verbs. The first are the future tense clitics fa(a)- (Nobiin) and b(i)- (Andaandi/Mattokki) from the Old Nubian verb ⲡⲁⲗ/ⲡⲉⲗ pal/pel ‘to come out’:

The second are the progressive/habitual clitics aa(g)- (Nobiin) and a- (Andaandi/Mattokki) from the Old Nubian verb ⲁⲕ ak ‘to sit, remain.’

Following an earlier proposal from Julien (2002), Fuß (2005: 209–14) proposes a syntactic solution to the development of agreement from subject clitic constructions in SOV languages. Whereas the subject clitic construction involves a complex “roll-up” including multiple leftward movement, the resulting surface order would then at a later stage of the language be reinterpreted as agreement. The drive behind the transition from a clitic to an agreement system would therefore be the reduction of movement and the simplification of the underlying syntactical structure.

Fuß’s solution is based on an analysis of subject agreement in the Mongolian SOV language Buryat, whose agreement suffixes clearly derive from independent nominative pronouns. This situation would be comparable to the subject agreement in contemporary Nile Nubian languages discussed above. Fuß’s shows that its ancestral language, classical Mongolian, allows for subject pronouns to appear in post-verbal positions, which would allow for development of subject clitics and later subject agreement in Buryat. Although we have no evidence of earlier stages of the Old Nubian language with full-fledged pronouns following verbal forms, it is evident that its series of subject clitics developed from pronominal elements.

He proposes the following syntactical reanalysis (Fuß 2005: 213):

Aside from the fact that we have no evidence of such a complicated syntactical movement in Old Nubian, it seems to conflict with our scrambling data, which suggest that scrambling is only possible with a topicalized subject, as in (5). If indeed the entire TP moves to SpecCP in order for the verb to adjacent to the subject clitic adjoined to C⁰, we lose the structural motivation for this correlation between scrambling and topicalization. Moreover, such an approach encounters difficulties when there appears to be cliticized material on the right of the subject clitic, as in the case of Old Nubian.

According to Zwicky & Pullum (1983: 504), only clitics can attach to material that already contains clitics. In the case of Old Nubian, this implies that both the predicate marker -a, as well as a number of discourse markers, including the focus marker (§4), should be analyzed as clitics as well.

Indeed, the predicate marker shows a low degree of host selectivity, marking whichever is the main predicate of the clause, whether nominal or verbal (van Gerven Oei 2015a). The following example shows this quite dramatically:

In (48) we find the predicate marker attached to nominal predicates such as amiskada, ‘judge-PRED’ and tōekkatta ‘power-ADJ-PRED,’ but also the verbal predicate osa derra minnalō ‘take.out-PRED apply-NEUT-PRED not.be-PRS.2/3SG-PRED-FOC.’ It also present on the adjunctive VP mataraŋa ‘witness-INCH-PRED.’ Additionally, the predicate marker appears within the scope of universal quantifiers, as in (6) kipta miššannon ‘people-PRED all-TOP,’ and functions as a vocative marker.

To assume that the predicate marker and the focus marker, as well as a number of other discourse markers, are structurally autonomous, which Fuß’s approach seems to imply, would lead to an explosion of the number of projections and movement involved to allow for adjacencies of the type proposed in (47). Moreover, we would encounter issues with the ordering of specific clitics, as for example in (26) where the subject clitic precedes the predicate marker and (29) where subject clitic appears to follow it.

In this paper, I have argued that the Old Nubian “personal endings” can best be analyzed as subject clitics, based on their syntactical distribution and morphology. They interact with other discourse markers in the sentence. Topicalization of the subject, marked by -eion, is correlated with the presence of a subject clitic on the main verb in order to license the subject trace. Conversely, focus marking of the subject by -lo signals that the subject has stayed in situ and is therefore correlated with the absence of a subject clitic. Subject clitics also appear in pro-drop constructions, and definite subjects that are neither topicalized nor focus-marked may be doubled by a subject clitic.

Although overall the diachronic syntactical model developed by Fuß (2005) is helpful to think through the transition from the Old Nubian subject clitic system to the agreement system of contemporary Nile Nubian languages, his purely syntactic approach clashes with several aspects of the Old Nubian clitic system, perhaps most problematically the distribution of the predicate marker -a. Conversely, a morpho-phonological approach such as proposed by Anderson (2005) may allow us to properly model the behavior of Old Nubian clitics, but lacks explanatory power on a diachronic scale.

In their broad overview of the different theoretical approaches to clitics, Spencer & Luís (2012: 231–32) suggest that a morphological approach à la Anderson may be more productive than a purely syntactic approach, “[w]hat seems clear, though, is that grammatical theory has to have some way of accommodating the fact that some clitics are exponents just of morphosyntactic properties while other clitics are exponents of representations with more semantic content, possibly even full-blown semantic predicates.”

To this important observation we should add that such a grammatical theory should come up with a convincing approach toward diachronic data as presented in this paper. If indeed a fully syntactic approach à la Fuß is too cumbersome, a morphological approach should be able to account for the forms of reinterpretation discussed above. Moreover, on a more general level, we need to continue to seek a complete account in which the reanalysis of subject clitics as agreement has been accompanied by the complete collapse of a rich discourse marking system.