The Crequy family originated the noble houses of Blanchefort, Bonne, Ricey, Blécourt, Canaples, Bernieulles, Hesmond, Tilly, Heilly, and Royon and some bastard branches, such as Lorins, Winnezeele[4] and Oudekerque.

The Crequy lineage seems to have engendered several small branches in villages of the Haut-Pays area such as Ambricourt, Coupelle-Vieille, Fruges,[5] Reclinghem, Wandonne,[6] Rimboval,[7] Dennebroeucq,[8] Douriez,[9] Capelle-lès-Hesdin, Guigny, La Loge, Montreuil, Sempy and Verchocq.

His wife, Mahaut, believing her husband was dead, was going to marry the Sire of Renty, whom Raoul found in his domains on his return to France.

His wife recognized him thanks to the bridal half-wedding ring that he wore, giving rise to the famous romantic poem of the Sire of Créquy,[11] in one hundred and seven quatrains.

By faithful service during the king's minority he had won the gratitude of Anne of Austria and of Mazarin, and in 1652 he became Duc de Créquy and a peer of France.

The latter half of his life was spent at court, where he held the office of first gentleman of the royal chamber, which had been bought for him by his grandfather.

He became, on the extinction of the elder branch of the family in 1702, Duc de Lesdiguires, and eventually succeeded to the honours of his younger brother François.

In 1667 he served on the Rhine, and in 1668 he commanded the covering army during Louis XIV's siege of Lille, after the surrender of which the king rewarded him with the marshalate.

After the death of Turenne and the retirement of Condé, he became the most important general officer in the army, but his overconfidence was punished by the severe defeat of Conzer Bruck (1675) and the surrender of Trier and his own captivity which followed.

But in the later campaigns of the Franco-Dutch War he showed himself again a cool, daring and successful commander, and, carrying on the tradition of Turenne and Condé, he was, in his turn, the pattern of the younger Generals of the stamp of Luxembourg and Villars.