Arnold V de Looz, (died August 22, 1327) was Count of Loon from 1279 to 1323 and Count of Chiny (Arnulf III) from 1299 to 1310. He was the son of John I, Count of Looz and Mathilde Jülich.
He helped Richardis Gelderland, his widow maternal grandfather, Henri, Count of Luxembourg and Renaud I, Count of Gelderland, fight Siegfried von Westerburg, archbishop of Cologne. Taken prisoner, he had to pay a ransom to be freed.
He was forced to deal with Isabelle de Conde, widow of his father in 1281 and had to assign a dower, and give Warcq, Agimont and Givet to his half-brothers John and Jacquemin. In turn, they give up their rights to the county of Loon. This is the only condition that the parents of Marguerite one hand, and his uncle Nicolas II de Conde on the other hand, consent to marriage.
In 1288, he commanded a corps of the army of John I, Duke of Brabant, and contributed much to the victory on June 5 in the famous Battle of Worringen (on the Rhine), which ended the War of Limburg succession between Renaud, Count of Gelderland, husband of Ermingarde heiress, Duchess of Limburg (+ 1283), and the Duke of Brabant.
he ranks in the war of Awans and Waroux between families Waroux and Awans, from 1297 to 1335, on the side of the bishops of Liege, Hugues de Chalon (from 1396-1301) and Adolph of La Marck (1313 to 1344), Haspengouw dependent on these princes. He was appointed regent Mambourg or Liège after the death of Adolf II of Waldeck (1302).
In 1299, death without his uncle's son Louis V, he inherited Chiny (is this uncle who organized in 1285 the famous Tournament Chauvency, Jacques Bretel celebrated).
In 1312, the death of the bishop of Liege Bar Thiebaut prompted him to return to Liege, but faces revolt of the bourgeoisie. The principality was ravaged and saw the excommunication of the count.