De Coucy, a noble family of northern France in the middle ages, named from the town and castle of Coucy, near Laon. The historical importance of the family, a branch of that of Vermandois, began at the close of the 11th century. The following are its more celebrated members. I. Thomas de (called Thomas de Marie), son of Enguerrand I., count of Amiens, died in 1130. Through his second wife he became lord of the castle of Montaigu, which he fortified and made the scourge of the surrounding country. Besieged by the neighboring nobles and by his own father, he was helped by Prince Louis, afterward Louis VI. (the Fat), the siege being raised in 1105. He afterward laid waste his father's territories with great ferocity. Having incited the cities of Amiens and Laon to revolt, he joined the king and his father against them, and ravaged the communes with unequalled atrocity. In 1116 he succeeded his father in possession of Boves, Coucy, and Amiens. Vanquished by Louis VI., he implored and obtained his pardon, but soon again provoked his anger, was besieged in Coucy, and was mortally wounded in a sortie.

II. Renand or Raonl de, castellan of Coucy, a minstrel, born about 1160. He went with the crusaders to the Holy Land in 1191, and was killed at Acre. He was the reputed author of 24 songs, remarkable for simplicity and tenderness, which were reprinted in 1830 under the editorship of Francisque Michel. He is the hero of a famous romance of the 13th century, which, under the title of Roumans dou chastelain de Coucy, was published in 1829. It is founded upon the following legend, which has been reproduced under various forms: Coucy was in love with a French lady, the wife of the chevalier de Fayel. Fighting in the ranks of the crusaders, he was mortally wounded, and deputed his servant to carry his heart to his mistress. The messenger was surprised by the husband, who caused the heart to be cooked and presented to his wife; she tasted it, but, being informed of the origin of the dish, starved herself to death. III. Enguer-rand III., killed by falling from his horse, and being pierced by his own sword, in 1242. He rebuilt the castle of Coucy, distinguished himself at the battle of Bouvines (1214), and was called "the Great." He is famous for his reputed saying, "Je ne suis roi ne duc, prince ne comte aussi; je suis le sire de Couci" which became the motto of his house.

One of his daughters married the Scottish king Alexander II. IV. Enguerrand VII., the last and most illustrious of the house, died near Brusa, Asia Minor, in 1397. He was early left an orphan, his father being killed at Crecy in 1346, and was carried by the victorious English to the court of Edward III., who gave him his daughter in marriage. He returned to Coucy in 1368 and restored his ruined estates. In the war that soon broke out between England and France he remained neutral. He fought for the pope in 1373 against the Milanese. In 1375 he asserted a claim to the possessions of the house of Hapsburg, in right of his mother Catharine of Austria, against his uncle, and gathered an army of vagabonds, with the encouragement of Charles V.; but after a campaign of unparalleled barbarity in Alsace, he was defeated by a body of Swiss, and his bandit army annihilated. He was subsequently chosen twice by the king to the delicate task of conciliating the turbulent Parisians. He fought in Flanders in 1382 and 1383, and in a futile invasion of Scotland. In 1390 he went with the duke de Bourbon in the Genoese expedition against Tunis, and in the unsuccessful siege of Afrikeah gained great honor.

He was employed on several embassies, and finally was given by the duke of Burgundy a sort of tutelage of his son the count de Nevers, one of the chiefs of the army for the relief of Hungary, then attacked by the Turks under Bajazet. Contrary to the judgment of Enguerrand and the other older commanders, a rash attack was made at Nicopolis, and the allied Christian army utterly defeated (Sept. 28, 1396). Enguerrand was taken prisoner, and died in captivity, his estates passing by sale to the house of Orleans.