iussisset
iussisset is a Latin form of iubeo, meaning “order, command”. It is the 3rd person singular pluperfect active subjunctive.
Found 102 times in the Latin texts on Socratos.
Where it is used
Caesar, De Bello Gallico 1.27.2: Qui cum eum in itinere convenissent seque ad pedes proiecissent suppliciterque locuti flentes pacem petissent, atque eos in eo loco quo tum essent suum adventum expectare iussisset, paruerunt.
All forms of iubeo (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.