Often, one of the first Italian language lessons beginners study is Italian subject pronouns (pronomi personali soggetto). Too often, however, there's a whole subset of Italian subject pronouns that is given scant attention, including egli, ella, esso, essa, essi, and esse.
Legacy Italian Subject Pronouns
Call them legacy subject pronouns or classic subject pronouns, these subject pronouns are still (infrequently) used in Italian. They typically appear only as regionalisms, in formal speech, or in literature. There are three pairs of Italian subject pronouns for the third person singular: egli/ella, lui/lei, esso/essa. The third person plural includes the pair essi/esse and the form loro, which is the same for both masculine and feminine.
Egli, Lui, Esso
Egli and lui are used with reference to people. Lui, especially in spoken language, can also refer to animals and things. Esso is used for animals and things.
Ho parlato con il direttore e egli but commonly lui mi ha assicurato il suo interessamento.
I spoke with the director and he assured me of his interest.
Cercai di trattenere il cavallo ma esso also lui proseguì la corsa.
I tried to hold back the horse but he continued on the course.
Un importante compito vi è stato affidato; esso dovrà essere eseguito nel miglior modo possibile.
An important task was entrusted to you; it must be performed in the best way possible.
Ella, Lei, Essa
The form ella has already fallen into disuse, especially in spoken language, and is considered literary and formal. Analogous to lui, the form lei also refers to animals and things, especially in spoken language. The form essa (unlike its masculine counterpart) also refers to a person, but it is less commonly used and has a literary or regional character.
Avverti tua sorella, forse essa but commonly lei non lo sa ancora.
Warn your sister, maybe she still doesn't know.
Ho cercato di prendere la gattina, ma essa also lei è scappata.
I tried to hold the kitten, but she ran away.
The plural forms essi and esse serve to indicate people, animals, and things. Loro is used with reference to people and, especially in spoken Italian, also to refer to animals.
Li ho guardati in viso, essi or loro abbassarono gli occhi.
I looked at them in the face, but they lowered their eyes.
All'ingresso della villa c'erano due cani; essi or loro stavano per mordermi.
At the entrance to the villa, there were two dogs; they were waiting to bite me.
Il Parlamento ha emanato nuove leggi; esse prevedono la modifica dell'ordinamento giudiziario.
Parliament issued new laws; they anticipate the modification of the legal rule.
Wherefore Art Thou, Italian Subject Pronouns?
The "forgotten" Italian subject pronouns egli, ella, esso, essa, essi, and esse, similar to the remote past tense (passato remoto), can sometimes seem obsolete, especially since they are often ignored in modern textbooks. A former grammatical rule held that egli was a subject pronoun and lui an object pronoun. But although lui, lei, and loro tend to predominate in colloquial conversation, egli, as well as the other subject pronouns in question, can still be found in literary texts. Similar to the remote past tense, the subject pronouns egli, ella, esso, essa, essi, and esse are still a feature of southern Italian dialects.
1a persona: io
2a persona: tu
3a persona maschile: egli, lui, esso
3a persona femminile: ella, lei, essa
1a persona: noi
2a persona: voi
3a persona maschile: loro, essi
3a persona femminile: loro, esse