venissent
venissent is a Latin form of venio, meaning “come”. It is the 3rd person plural pluperfect active subjunctive.
Found 150 times in the Latin texts on Socratos.
Where it is used
Caesar, De Bello Gallico 1.31.10: … rte tertia Sequanos decedere iuberet, propterea quod paucis mensibus ante Harudum milia hominum XXIIII ad eum venissent, quibus locus ac sedes pararentur.
Terence, Heautontimorumenos 2.2.231: Venissent: sed vereor ne mulier me absente hic corrupta sit.
Livy, Ab urbe condita 1.9.13: turbato per metum ludicro maesti parentes uirginum profugiunt, incusantes uiolati hospitii foedus deumque inuocantes cuius ad sollemne ludosque per fas ac fidem decepti uenissent.
All forms of venio (conjugation table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Lewis & Short, A Latin Dictionary (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.