Editing Latin declension (section)

== Grammatical cases ==
A complete Latin noun declension consists of up to seven [[grammatical cases]]: [[nominative]], [[vocative]], [[accusative]], [[genitive]], [[dative]], [[ablative]] and [[locative]]. However, the locative is limited to a few nouns: generally names of cities, small islands and a few other words.

===Order of cases===
The Roman grammarian [[Aelius Donatus]] (4th century AD), whose work was used as standard throughout the Middle Ages, placed the cases in this order:

:{{lang|la|casus sunt sex: nominativus, genetivus, dativus, accusativus, vocativus, ablativus.}}<ref>[https://archive.org/details/corpusgrammatico01linduoft/page/n28/mode/1up Aelius Donatus, ''Ars Major'', 2.8.]</ref>
:"there are six cases: nominative, genitive, dative, accusative, vocative and ablative."

This order was based on the order used by earlier Greek grammarians, with the addition of the ablative, which does not exist in Greek. The names of the cases also were mostly translated from the Greek terms, such as {{lang|la|[[wikt:accusativus#Latin|accusativus]]}} from the Greek {{lang|grc|[[wikt:αἰτιατικός|αἰτῐᾱτῐκή]]}}.

This traditional order was formerly used in England, such as in ''The School and University Eton Latin Grammar'' (1861).<ref>Mongan, James Roscoe (1861). ''The School and University Eton Latin Grammar, Explanatory and Critical''. London 1861.</ref> That order is still followed in most other European countries. Gildersleeve and Lodge's ''Latin Grammar'' (1895) also follow this order. More recent Latin grammars published in the United States, such as Allen and Greenough's ''New Latin Grammar'' (1903) and ''[[Wheelock's Latin]]'' (first published in 1956) follow this order except they list the vocative last.

However, in Britain and countries influenced by Britain other than the United States, the Latin cases are usually given in the following order: nominative, vocative, accusative, genitive, dative, ablative. This order was introduced in [[Benjamin Hall Kennedy]]'s ''Latin Primer'' (1866), with the aim of making tables of declensions easier to recite and memorise (the first three and the last two cases having identical forms in several declensions).{{Full citation needed|date=July 2023}} It is also used in [[France]]<ref>Paul Crouzet (1902), ''Grammaire Latine, simple et complète'', p. 7.</ref> and [[Belgium]]. In [https://www.youtube.com/watch?v=v6rLLE48RL0 ''Rosa''] (1962), a song in French by the Belgian singer [[Jacques Brel]], Brel sings the declension of "rosa" as {{lang|la|rosa, rosa, rosam}}, following the British order of cases.{{Full citation needed|date=July 2023}}

===Syncretism===
<!--is there a better way to logically organize this section, or at least add a (small!) color-coded chart as a visual aid?-->
[[Syncretism (linguistics)|Syncretism]], where one form in a paradigm shares the ending of another form in the paradigm, is common in Latin. The following are the most notable patterns of syncretism:

====Gender-specific====
* For neuter nouns, the nominative, vocative, and accusative cases are identical. The nominative, vocative, and accusative plural almost always ends in ''-a''. (Both of these features are inherited from [[Proto-Indo-European]], and so no actual syncretism is known to have happened in the historical sense, since these cases of these nouns are not known to have ever been different in the first place.)

====Case-specific====
* The vocative form is always the same as the nominative in the plural, and usually the same as the nominative in the singular except for second-declension nouns ending in ''-us'' and a few nouns of Greek origin. For example, the vocative of the first-declension {{wikt-lang|la|Aenēās}} is {{lang|la|Aenēā}}.
* The genitive singular is the same as the nominative plural in first-, second-, and fourth-declension non-neuter Latin nouns.
* The dative singular is the same as the genitive singular in first- and fifth-declension pure Latin nouns.
* The dative is always the same as the ablative in the singular in the second declension, the third-declension full ''i''-stems (i.e. neuter ''i''-stems, adjectives), and fourth-declension neuters.
* The dative, ablative, and locative are always identical in the plural.
* The locative singular is identical to the genitive in the 1st and 2nd declensions; to the dative or ablative in the 3rd declension; to the ablative in the 5th declension.
* The nominative and accusative plurals are identical for all nouns of the 4th declension (in ''-ūs'') and 5th declension (in ''-ēs''), and for many nouns of the 3rd declension (in ''-ēs''; but a distinct accusative plural in ''-īs'' can be used in Classical Latin for some i-stem nouns).

=== History of cases ===
[[Old Latin]] had essentially two patterns of endings. One pattern was shared by the first and second declensions, which derived from the Proto-Indo-European [[Thematic vowel|thematic]] declension. The other pattern was used by the third, fourth and fifth declensions, and derived from the athematic PIE declension.