Old Dominion's coat of arms

[scrabulista]

When Virginia was colonized in the early 17th century, its coat of arms read, "En Dat Virginia Quintum," which indicated that it was the fifth of the king's domains at the time — after England, Scotland, France, and Ireland. (The seal was altered slightly in the 18th century to read "En Dat Virginia Quartam," after England and Scotland united as the kingdom of Great Britain.)

The English Colonial Experiment: Virginia and Massachusetts Tutorial | Sophia Learning

The English Colonial Experiment: Virginia and Massachusetts

We explain The English Colonial Experiment: Virginia and Massachusetts with video tutorials and quizzes, using our Many Ways(TM) approach from multiple teachers.<p>Identify the unique features associated with early English colonies in North America.</p>

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Is this Latin or something else? Virginia gives a fifth (to England?) But England in Latin is Anglia.
En can also be an interjection.
Is it part of a longer sentence?

 

[Pacifica]

Is this Latin or something else?

It is Latin.

En can also be an interjection.

That's what it is here and what it usually is as a Latin word.

Is it part of a longer sentence?

I don't know but it need not be. It works as a complete sentence by itself. "Lo! Virginia gives a fifth!"—that is, a fifth domain for the Crown.

 

[scrabulista]

The shift from Quintum to Quartam could be something like dominium vs. patria?

 

[Pacifica]

More like terram, I guess.

 

[Pacifica]

Apparently there was also a version with Quintam:

Old Dominion - Encyclopedia Virginia

A popular and plausible tradition that appears in most histories and reference works is that referred to Virginia as his loyal old dominion at the time that he was restored to the throne in 1660. After the Parliamentarians executed in 1649 following their victory in the English Civil...

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