Another question related to my geography of the Roman Empire which I am writing has arisen: during the time of Trajan, 117 AD, there were several provinces which had names in the plural, especially those which bordered or resided on the Alps, to name a few:
- Alpēs Maritimae
- Alpēs Cottiae
- Alpēs Grāiae et Poenīnae
In my geography itself, I have written several phrases similar to the following, note that the verbs are in the singular number:
Prīma hārum prōvinciārum, Alpēs Maritimae, ut nōmen dīcit, plūrimē montēs continet et lītora prope Ligusticum Mare.
I wrote down the verbs in the singular while writing because it made sense to me; despite the fact that the names themselves are in the plural, they refer to singular things, provinces. However, as pointed out by @JoonasIlmavirta in CONLOQVIVM, this might not be the case.
To sum up: when a name (or noun) has a plural form but refers to a singular thing, should any verb of which the name (or noun) is a subject be in the singular or plural?