Temporal Clauses
Temporal clauses in Latin answer when, while, before, after, until — and the conjunction alone almost never tells you the answer.
Cum, postquam, ubi, dum, donec, antequam, priusquam each pick between indicative and subjunctive based on whether you're stating a bare fact or coloring it with circumstance, anticipation, or purpose.
The trap that catches every reader: cum. With the indicative it dates the time ("when"); with the imperfect or pluperfect subjunctive in past narrative it usually shades into "since" or "although." Same word, same English gloss tempting you, completely different logic.
Treat the conjunction as a question — what mood does it want here? — and the rest of the system falls into place.
Pick the mood by what the writer is doing — stating a fact, anticipating, or coloring with cause/concession.
Mood, not conjunction, carries the meaning. Train the eye on the verb, not the cum.
See It In Action
— Cic. Fam. ix. 18. 1
Classic narrative cum: imperfect subjunctive in the cum-clause sets the surrounding circumstance; the perfect indicative in the main clause carries the actual event.
— Sall. Cat. 11
Postquam with the perfect indicative: a clean, completed prior fact. No mood drama — the soldiers won, then this happened.
— Caes. B. G. i. 46
Dum + present indicative inside past narrative — translate with the English imperfect ("was going on"), not a literal present. This is the historical present at work.
— Caes. B. G. i. 53
Prius … quam split into its two parts and uses the perfect indicative because reaching the river actually happened. Subjunctive here would have meant "before they could reach it."
"when X happened, Y" — flat statement of time
cum audīvī, laetātus sum = "when I heard, I rejoiced"
"when / while X was happening, Y" — Y is the main event, X the setting
cum essem in Tusculānō, accēpī litterās = "when I was at Tusculum, I got the letter"
"since X, Y" — X explains why Y happened
cum tantum equitātū valeāmus, id facile est = "since we have so much cavalry, that's easy"
"although X, Y (still / nevertheless)" — usually with tamen in the main clause
cum prīmī concidissent, tamen reliquī resistēbant = "though the front had fallen, the rest still held"
"X had hardly happened when Y" — flip the English so the cum-clause becomes the dramatic main event
diēs nōndum decem intercesserant, cum necātur = "barely ten days had passed when he was killed"
Same conjunction, opposite jobs. Indicative dates the moment; past subjunctive describes the surrounding cause or concession.
"at the moment that…" — pure time
cum occīditur, fuērunt
when he is killed, they were on the spot
"since / although…" — describes circumstance
cum essem ōtiōsus, accēpī
since/while I was at leisure, I received
Tip: Ask: is the cum-clause merely DATING the main action, or COLORING it with cause or concession? Imperfect/pluperfect subjunctive in past narrative almost always means the second.
In cum prīmī ōrdinēs concidissent, tamen ācerrimē reliquī resistēbant (B. G. vii. 62), how should the cum-clause be translated?
Study Tips
- •Build a one-page mood chart — for each conjunction, list "indicative when " and "subjunctive when ." Cum and priusquam are the only entries that really fight you.
- •Whenever you see cum + imperfect or pluperfect subjunctive in narrative, try translating with "since" or "although" before "when" — it's right more often than you'd think.
- •For dum + present indicative inside a past story, translate with the English imperfect ("while he was speaking"), not a literal present. The Latin is using the historical present.
- •Drill the antequam / priusquam split on Caesar: indicative when something actually happened first, subjunctive when something almost happened or was prevented from happening.