The Declension of the English Declension

The English language once had an extensive declension system similar to modern German or Icelandic. Old English distinguished between the nominative, accusative, dative, genitive, and instrumental cases. Declension fell into disuse during the Middle English period when accusative and dative pronouns merged into a single objective pronoun. Modern English no longer uses declension, except for remnants of the former system in a few pronouns.

Evolution (or Devolution) of the English Declension

Interrogative Pronouns

Case_______Old English__Mid. English__Modern English

Nominative:______hwā__________who____________who

Accusative:___hwone / hwæne____whom___________whom

Dative:______hwām / hwǣm _____whom___________whom

Instrumental:__hwȳ / hwon______whom___________whom

Genitive:_______hwæs__________whos___________whose

As one can see, the accusative, dative, and instrumental cases have combined in English to form the objective interrogative pronoun, "whom". In Modern English speech, it is common for one to hear "who" when it should be "whom". This is just another example of the declension of the English declension.

In personal pronouns, there is still a declension, but the accusative and dative have merged in Modern English and the instrumental does not apply in this aspect. So for first person singular, one would see "I" as nominative, "me" as accusative or dative, and "my" as genitive. This pattern is followed for every personal pronoun in Modern English.

Now as for the declension of nouns and adjectives, this is very rare in English. Nouns are declined normally when they are pluralized in English so the syntactic variations of "book to books" would be an example of a nominal declension:

Nominal Declension

ox-singular
oxen-plural

Another nominal declension is one borrowed from French. It distinguishes between masculine and feminine in this case. All English nouns like the examples below have been borrowed from another language—usually French or Latin because each one distinguishes between gender:

Rare Nominal Declension

Masculine singular: alumnus/fiancé
Feminine singular: alumna/fiancée
Masculine plural: alumni/fiancés
Feminine plural: alumnae/fiancées
Neuter singular: alumnus/fiancé
Neuter plural: alumni/fiancés

Then there are of course the adjective declensions. In Modern English, this is very rare. In Modern French, it's very common such as the difference between "nouveau" and "nouvel" and "nouveaux" and so on. For English, though, we can only see this in borrowed words, mainly French words like the one below:

Rare Adjectival Declension

Masculine: blond
Feminine: blonde
Neuter: blond

This is a pretty easy thing to grasp in English because declining nouns, pronouns, and adjectives is really a premise for the days of yore. I hope that this might have helped you out in understanding it in Modern English.