It is an extremely densely populated region with some 4 million inhabitants - 7% of France's total population, making it the fourth most populous region in the country - 83% of whom live in urban communities. Its administrative centre is the city of Lille. The second largest city is Calais which serves as a major continental economic hub with Dover, England of Great Britain 35 miles away and the white cliffs of Dover, England are visible from Calais on a clear day. Other major towns include Valenciennes, Lens, Douai, Béthune, Dunkerque, Maubeuge, Boulogne-sur-Mer, Arras, Cambrai and Saint-Omer.
During the 4th and 5th centuries, the Roman practice of coopting Germanic tribes to provide military and defense services along the route from Boulogne to Cologne created a Germanic-Romance linguistic border in the region that persisted until the 8th century. By the 9th century most inhabitants north of Lille spoke a dialect of Middle Dutch, while the inhabitants to the south spoke a variety of Romance dialects. This linguistic border is still evident today in the place names of the region. Beginning in the 9th century, the linguistic border began a steady move to north and the east. By the end of the 13th century the linguistic border had shifted to the river Lys in the south and Cap-Griz-Nez in the west.
During the Middle Ages, the Pas-de-Calais department comprised County of Boulogne and the County of Artois, while Nord department is mostly made up of the southern portions of the County of Flanders and the County of Hainaut. Boulogne, Artois, and Flanders were fiefs of the French crown, while Hainaut was within the Holy Roman Empire. Calais, from 1347 to 1558, when it was recovered by the French throne, was an English possession. In the 15th century all of the territories, except Calais, were united under the rule of the Dukes of Burgundy, along with other territories in northern France and areas in what is now Belgium, Luxembourg, and the Netherlands. With the death of the Burgundian duke Charles the Bold in 1477, the Boulonnais and Artois were seized by the French crown, while Flanders and Hainaut were inherited by Charles's daughter Marie. Shortly thereafter, in 1492, Artois was ceded back to Marie's son Philip the Handsome, as part of an attempt to keep Philip's father, Emperor Maximilian I, neutral in French King Charles VIII's prospective invasion of Italy.
Thus, most of the territories of what is now Nord-Pas de Calais were reunited to the Burgundian inheritance, which had passed through Marie's marriage to the House of Habsburg. These territories formed an integral part of the Seventeen Provinces of the Netherlands as they were defined during the reign of Philip's son, Emperor Charles V, and passed to Charles's son, Philip II of Spain. When the Netherlands revolted against Spanish rule, beginning in 1566, the territories in what is now Nord-Pas de Calais were those most loyal to the throne, and proved the base from which the Duke of Parma was able to bring the whole southern part of the Netherlands back under Spanish control.
During the wars between France and Spain in the 17th century (1635-1659, 1667-1668, 1672-1678, 1688-1697), these territories became the principal seat of conflict between the two states. French control over the area was gradually established - Artois was annexed in 1659, and most of the current Nord department had been acquired by the Treaty of Nijmegen in 1678. The current borders were mostly established by the time of the Treaty of Ryswick in 1697.
The area, previously divided among the French provinces of Flanders, Artois, and Picardy, was divided into its present two departments following the French Revolution of 1789. Under Napoleon I the French boundary was extended to include all of Flanders and present-day Belgium until the Treaty of Waterloo in 1815 restored the original French boundary.
During the 19th century, the region underwent major industrialisation and became one of the leading industrial regions of France, second only to Alsace-Lorraine. Nord-Pas de Calais was barely touched by the Franco-Prussian War of 1870; indeed, the war actually helped it to cement its leading role in French industry due to the loss of Alsace-Lorraine to Germany. However, it suffered catastrophic damage in the two World Wars of the 20th century. In the First World War, much of the region was occupied by Germany. Many of its towns and hundreds of square miles of land were wrecked in four years of trench warfare, with the region suffering more damage than any other part of France. Germany occupied it again in the Second World War and used the region as a launching base for attacks on England by the Luftwaffe and the V-1 and V-2 missile systems. Heavy Allied bombing and fighting on the ground again devastated many of the region's towns. Although most of the region was liberated in September 1944, Dunkirk was not liberated until 9 May 1945, making it the last French town to be freed from German occupation. The region's conflicted history is memorialised in numerous war cemeteries and memorials, such as the Vimy Memorial at Vimy Ridge, which is Canada's most important memorial to its fallen soldiers.
Since the war, the region has suffered from severe economic difficulties (see Economy below) but has benefitted from the opening of the Channel Tunnel and the growth in cross-Channel traffic in general.
In addition, the region's ethnic diversity has been affected by repeated waves of immigrant workers from abroad - Belgians and Welsh from Britain before 1910; Poles, Czechs, Italians and Portuguese in the 1920s and 1930s; North Africans, Greeks and Yugoslavians since 1945; some thousand descendants of Chinese and Vietnamese ditch diggers and railroad crews hired by French government contractors in World War I; a small population of Turks since the 1960s settled in the region; and large cities like Lille, Calais and Boulogne-sur-Mer are home to sizable Briton, Scandinavian, Sub-Saharan African and Latin American immigrant/descendant communities.
The French state has also sought to boost the region's relatively neglected culture; in 2004, it was announced that a branch of the Louvre would be opened in the city of Lens. For decades, the Nord/Pas-de-Calais was thought of as culturally conservative, but the region currently has liberal tendencies. In the early 2000s, the leftist French Green Party won the largest number of votes to nearly carry a majority in regional and local representation. The Greens managed to attract many conservative voters from small towns and farmers.
The region's religious profile is representative of France with the majority (85%) being Roman Catholic, but not every member regularly attends church or practices every element of Catholicism. Other Christian groups are found in the region: Protestants, Eastern Orthodox and Mormons have a few churches. North Africans have introduced Islam to the region, and there are also small but growing communities of Buddhists and Hindus in recent years. In World War II, 18,000 of the region's French Jews were victims of the Nazi occupation, but the small Jewish community remains active as it has for hundreds of years.