Vital manoeuvres supported an Estonian neighbour (7)

I believe the answer is:

latvian

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But I can't explain it at all! Could you help me understand?

(Other definitions for latvian that I've seen before include "Riga resident" , "Valiant (anag) - from Riga?" , "One from Riga" , "of a recently liberated state" , "Baltic language" .)

I've seen this clue in the Sydney Morning Herald.

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