Bourbourg (Dutch: Broekburg) is a commune in the Nord department in northern France. It is situated in the maritime plain of northern France, in the middle of a triangle formed by Dunkirk, Calais, and Saint-Omer.

In the second half of the 3rd century AD the North Sea broke through the sand dunes to the Flemish coast in an event known as attributed to the second Dunkirk Transgression. Then in 7th century siltation of the sea intrusion created a vast coastal swamp with some dry areas. This enabled local residents between the 7th and the 12th century to begin to use the areas resources base on the polder model.

The first mention of Bourbourg is in 1035AD although the settlement is probably older, possibly even from the end of the 9th century. The oldest part of the city is located immediately southwest of the parochial St. John's Church, and the town was proabably part of Flemish defensive line against the Normans.

The Church Saint-Jean-Baptiste was founded by Clementia of Burgundy, Countess of Flanders, in 1100AD and just south of the city a Benedictine monastery, (St Mary's Abbey) was established by her husband Robert II of Jerusalem. After a while it became the custom in that monastery that only nuns of noble descent could join, which gave it the name "Abbey of noble ladies". In 1104AD, the city was named as a fortress and become the Centre of a Castellan domain of the same name. The Castallans domain was approximately 12,700 ha in 1071AD and had 10 villages in a triangle between the North Sea, the Aa river and the Lemonades-Loon line.

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