Lesson 4: Cum Clauses

Master all five uses of cum with the subjunctive and indicative, including the tricky cum inversum.

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Overview

The Latin conjunction cum (sometimes spelled quum in older texts) is one of the most versatile words in the language. It can mean "when," "since," "although," or "at the time when" — and the choice of mood (indicative vs. subjunctive) plus the presence of tamen or other particles determines which meaning applies. Reading Caesar or Livy without mastering cum clauses is nearly impossible: the construction appears hundreds of times.

The Five Uses of Cum

Use Mood Tense of main verb Signal Meaning
1. Temporal (simple) Indicative Any (none) "when" (pure time)
2. Temporal-circumstantial Subjunctive Imperfect or pluperfect (none) "when" (with context)
3. Causal Subjunctive Any (none; context) "since, because"
4. Concessive Subjunctive Any tamen in main clause "although"
5. Cum inversum Indicative Imperfect (main verb) cum subito "when suddenly"

Use 1: Temporal cum + Indicative

Meaning: A simple, precise "when" — a time at which. The cum clause states a specific moment, and the indicative signals that the writer is simply noting the time without additional nuance.

Characteristic: Usually in primary tenses (present, future, perfect when not narrative). The main verb and the cum verb often share the same tense.

Cum Caesar vēnit, omnēs gavīsī sunt. When Caesar came, everyone rejoiced.

Cum Rōmae eram, cotīdiē in forum ībam. When I was in Rome, I used to go to the forum every day.

When to use: If cum introduces a clause with a present or future tense indicative, it is almost certainly simple temporal. Also used in repeated or habitual actions (cum + imperfect indicative or present indicative).

Use 2: Temporal-Circumstantial cum + Subjunctive

Meaning: "When" — but now the cum clause provides the background circumstances surrounding the main action. This is the most common use of cum in Caesar and Livy. The subjunctive signals that the subordinate clause is not just noting a time but describing the situation within which the main event occurred.

Characteristic: The cum clause typically carries an imperfect or pluperfect subjunctive (secondary sequence, since narrative is past). The main verb is often a perfect indicative.

Cum Caesar Rōmam vēnisset, senātus eum laudāvit. When Caesar had come to Rome, the senate praised him. (Background: Caesar's arrival; foreground: senate's praise)

Cum hostēs trānsīrent, lēgātī adventāvērunt. When the enemy were crossing, the envoys arrived. (The crossing is background context for the envoys' arrival)

Caesar's preferred pattern:

  • cum + pluperfect subjunctive (prior background) / main verb perfect indicative
  • cum + imperfect subjunctive (simultaneous background) / main verb perfect indicative

Use 3: Causal cum + Subjunctive

Meaning: "Since" or "because." The cum clause gives the reason for the main clause. The subjunctive signals that the cause is presented from the author's (or speaker's) perspective — it's an asserted reason, not just a stated fact.

Cum id scīret, tacuit. Since he knew this, he kept silent.

Cum Caesar tardius venīret, Ariovistus respondit... Since Caesar was arriving rather slowly, Ariovistus replied... (Caesar BG 1.34 style)

How to tell causal from temporal-circumstantial: Context is key. Ask: Does the cum clause explain why the main event happened? If yes → causal. If it simply sets the scene → temporal-circumstantial. Causal cum often has id, hoc, quod as connectives, or the reasoning is explicit.

Use 4: Concessive cum + Subjunctive

Meaning: "Although." The cum clause concedes something that might seem to argue against the main clause, but the main clause happens anyway.

Characteristic: The main clause almost always contains tamen ("nevertheless") or tum ("still"). The combination cum...tamen is the clearest signal of concessive cum.

Cum hostēs fortēs essent, tamen victī sunt. Although the enemy were brave, they were nevertheless defeated.

Cum multum valuisset, tamen in hāc rē lāpsus est. Although he had been very influential, he still failed in this matter.

Cicero, Cat. 2.1: Cum in hāc victōriā... laetēmur, tamen... Although we rejoice in this victory... nonetheless...

Mnemonic: Spot tamen in the main clause → look back for cum → concessive.

Use 5: Cum Inversum (Inverted Temporal)

Meaning: "When suddenly." This is a special construction where the main clause comes first, describing what someone was doing, and the cum clause introduces a sudden interruption. The word subito ("suddenly") or ecce ("behold") often appears in or near the cum clause.

Characteristic: Main verb = imperfect indicative (ongoing action); cum clause verb = perfect indicative (the sudden interruption).

Haec faciēbat cum subitō nūntius advenīt. He was doing these things when suddenly a messenger arrived.

In forō ambulābam cum Cicerōnem vīdī. I was walking in the forum when I saw Cicero.

Caesar in castrīs manēbat cum subitō hostēs impetum fēcērunt. Caesar was remaining in the camp when suddenly the enemy launched an attack.

Why "inverted"? Normally the cum clause comes first and sets the scene. Here, the cum clause is the surprising foreground event that interrupts the main clause's background action. The order is reversed.

Full Set of Worked Examples from Authentic Latin

1. Temporal (indicative) — Caesar, BG 1.7:

Cum hī nūntiī ad Caesarem veniunt, ipse aberat. When these messengers came to Caesar, he himself was absent.

2. Temporal-circumstantial — Caesar, BG 1.11:

Cum in eam sententiam plērīque pedibus īssent, subitō Considius... nuntiavit. When most had gone over to that opinion, suddenly Considius reported...

3. Temporal-circumstantial with pluperfect — Caesar, BG 2.4:

Cum ab hīs quaesīvisset quae civitātēs... armātae essent... When he had asked them which states were armed...

4. Causal — Cicero, Cat. 1.2:

Cum tē... ēicere dēbeāmus, tamen nōs... loquimur. Since we ought to drive you out, we nevertheless speak...

5. Causal — Caesar, BG 1.3:

Cum esset Orgetorix... cīvitātī suāsit. Since Orgetorix was [the most distinguished], he persuaded the state...

6. Concessive — Caesar, BG 3.19:

Cum plūrimum potuisset, tamen... nōn dubitāvit. Although he had been very powerful, he did not hesitate...

7. Concessive — Cicero:

Cum id possem, nōlēbam; cum vellō, nōn possum. Although I was able to, I didn't want to; although I want to, I can't.

8. Cum inversum — Livy:

Haec agitābant cum repente nūntiī... They were discussing these things when suddenly messengers...

9. Cum inversum — Caesar, BG 5.26:

Hīs rēbus gestīs, cum... essent, subito Ambiorix cum equitātū apparuit. While these things were being done, suddenly Ambiorix appeared with his cavalry.

10. Temporal-circumstantial vs. causal contrast:

Cum Caesar profectus esset, Rōmā discessimus. (temporal-circumstantial: "after/when Caesar had set out, we left Rome") Cum Caesar profectus esset, Rōmā discēdere dēbuimus. (causal: "since Caesar had set out, we had to leave Rome")

11. Nested cum clauses — Cicero, Verr.:

Cum haec ita sint, cum hōc sciātis, tamen tacētis? Since these things are so, since you know this, do you still remain silent?

12. Cum + pluperfect subjunctive, historical — Livy 1.7:

Cum huc atque illuc iniret, nec exitum reperiret... When he had gone here and there and could find no way out...

Decision Tree: Identifying cum Clause Type

See "cum" + subordinate clause
        |
        v
Is the subordinate verb INDICATIVE?
   YES → Is the main verb imperfect? And is there a sudden event?
            YES → Cum inversum ("when suddenly")
            NO  → Temporal cum (simple "when")
   NO (subjunctive) →
        |
        v
Is "tamen" (or "tum") in the main clause?
   YES → Concessive ("although")
   NO  →
        |
        v
Does the cum clause explain WHY the main event happened?
   YES → Causal ("since, because")
   NO  → Temporal-circumstantial ("when," with background context)

Practice Exercises

Exercise A — Identify the cum clause type

  1. Cum Caesar loquērētur, tamen mīlitēs fremebant. → Concessive
  2. Haec faciēbat cum hostēs advēnērunt. → Cum inversum
  3. Cum id sciēbam, tacēbam. → Temporal (indicative)
  4. Cum multōs annōs regnāvisset, mortuus est. → Temporal-circumstantial
  5. Cum pauper esset, tamen honestus erat. → Concessive
  6. Cum hoc nescīret, errāvit. → Causal

Exercise B — Choose indicative or subjunctive

Explain your choice:

  1. Cum Caesar Rōmam vēn___ (venīre), senātus eum salūtāvit. → vēnisset — temporal-circumstantial (past narrative, background context)

  2. Haec scrībēbam cum tū ___ (venīre — perfect indicative). → vēnistī — cum inversum

  3. Cum dux fortis ___ (esse), tamen victus est. → esset — concessive (note tamen)

Exercise C — Translate

  1. Cum exercitus profectus esset, Caesar in castrīs manēbat.
  2. Epistulam scrībēbam cum subitō Marcellus intrāvit.
  3. Cum id facere nōn posset, adiutōrem rogāvit.

Summary Reference Card

Cum type Mood Key signal Translation
Temporal (simple) Indicative none "when"
Temporal-circumstantial Subjunctive (imperf/pluperf) Past narrative context "when"
Causal Subjunctive Reason implied "since, because"
Concessive Subjunctive tamen in main clause "although"
Cum inversum Indicative cum subitō; main verb imperfect "when suddenly"