In 1798 Vial was part of the Armée d'Orient sent on expedition to Egypt and Syria, commanding a brigade in the division of Jacques-François Menou. After Menou was wounded taking Alexandria, Vial replaced him as division commander, leading it at the Battle of the Pyramids. He acted as provincial administrator of Damietta and Mansoura before joining the ultimately unsuccessful Siege of Acre (1799) and seeing action at Mount Tabor. He returned to France in December 1800.