Raoul Victor Patrice Castex (27 October 1878, Saint-Omer – 10 January 1968, Villeneuve-de-Rivière) was a French Navy admiral and a military theorist.
The same year, he founded the Institut des hautes études de la défense nationale, which he headed until 1939.
He rose to vice-amiral in 1937 and finished his career heading the naval forces of the Northern fleet.
One of his main achievements was the creation of the Institut des Hautes Études de la Défense Nationale (IHEDN, Institute of Higher Studies of National Defence), which aimed to reduce the intellectual gap between civilian and military officials.
Between 1929 and 1939, Castex wrote Théories stratégiques, which analysed the link between land and naval warfare and argued for a national "gravity centre", which, in the case of France, would be situated outside Europe.