Passage: However, on 15 May 392, the Western Emperor Valentinian II was found dead at his residence in Vienne, Gaul. Valentinian had continued the imperial policy of suppressing the interests of adherents of the old pagan religions while supporting Christians. This policy had resulted in increasing tensions between the emperor and the senators. Arbogast, was the magister militum, or military commander, of the Western Empire and its de facto ruler. After Valentinian's death he informed Theodosius, the Eastern Emperor that the young emperor had committed suicide.

Question: How did the young emperor die?
suicide