Dieppe is a Canadian city in Westmorland County, New Brunswick. It is New Brunswick's fourth most populous city with a history and identity that goes back to the eighteenth century. It was first incorporated as a town in 1952 and designated as a city in 2003. Its namesake comes from a commune in the Seine-Maritime department, a port on the English Channel, in France and was adopted by the citizens of the area in 1946 to commemorate the Second World War's Operation Jubilee, the Dieppe Raid of 1942.