Kaya Alp
Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
Louis II, Count of Blois
Louis II of Châtillon( d. 26 August 1346, battle of Crécy), son of Guy I, Count of Blois and Margaret of Valois, was count of Blois and lord of Avesnes 1342 – 1346.
In 1340 in Soissons, he married Jeanne of Avesnes, Countess of Soissons( d. 1350), daughter of John of Avesnes, Lord of Beaumont.
They had three children:
Louis was killed at the Battle of Crécy.
Matthew I of Montmorency
Matthew I( died 1160) was lord of Montmorency, Marly, Conflans- Sainte- Honorine and Attichy.
He was also Constable of France from 1138 to 1160 under Louis VII.
He was the eldest son of Bouchard IV de Montmorency and Agnes de Beaumont- sur- Oise.
In 1126 he married Alice FitzRoy( Alix), illegitimate daughter of King Henry I of England, and had the following issue: Alix died before 1141 when her husband married his second wife Adelaide of Maurienne, the widow of Louis VI of France.
Beatrice d'Avesnes
Beatrice d' Avesnes( died: 1321) was a daughter of Baldwin of Avesnes and his wife Felicitas of Coucy.
Baldwin was the son of Bouchard IV of Avesnes.
She married in 1265 Count Henry VI of Luxembourg and was the mother of:
Lyon Cohen
Lyon Cohen( 1868–1937) was a Polish- born Canadian businessman and a philanthropist.
He was the grandfather of singer/ poet Leonard Cohen.
Bouchard IV of Avesnes
Burchard IV or Bouchard IV (1182–1244) was the lord of Avesnes and Étrœungt.
He was the son of James of Avesnes and Adela of Guise and brother of Walter, Count of Blois.
Bouchard began his career as a cantor and subdeacon in the church of Laon.
In 1212, he was named bailiff of Hainaut.
In this capacity, he served as tutor and guardian of the young Margaret, sister of Joanna, Countess of Flanders and Hainault.
He later married Margaret in 1212, though she was only ten years old and the marriage could not be consummated.
Neither Joanna nor Count Ferdinand gave their consent, and tried to have the marriage stopped, they failed.
Bouchard lived a war-like life.
He invaded the territory of his brother Walter, who had received most of their patrimony.
He then invaded Flanders and forced Joanna and Ferdinand to recognise his marriage to Margaret.
He then fought at the Battle of Bouvines in 1214, under the (losing) Flemish banner.
Philip Augustus, the king of France and victor of Bouvines, then counselled the pope, Innocent III, to declare the marriage of Bouchard and Margaret illegal.
Innocent eventually excommunicated Bouchard on 19 January 1216.
They took refuge in Luxembourg.
In 1219, Bouchard was captured in battle and would be imprisoned in Ghent for two years.
To obtain his release, Margaret accepted the dissolution of the marriage and Bouchard left for Italy to fight for the Holy See.
Upon his return, he was decapitated at Rupelmonde on the orders of Joanna.
Bouchard and Margaret had three children, who played an important part in the War of the Succession of Flanders and Hainault:
James of Avesnes
James (also "Jacques" or "Jacob"; 1152 – 7 September 1191) was a son of Nicholas d'Oisy, Lord of Avesnes and Matilda de la Roche.
He was the lord of Avesnes, Condé, and Leuze from 1171.
In November 1187, James joined the Third Crusade as leader of a detachment of French, Flemish, and Frisian crusaders arriving by ship on the Palestinian coast near Acre around 10 September 1189.
James and his men came as military reinforcements for the Siege of Acre.
At the Battle of Arsuf, James was thrown from his saddle and, after slaying fifteen enemy warriors, was himself cut down.
The next day, a search party of Hospitallers and Templars found his body on the battlefield.
It was taken back to Arsuf and buried there in a ceremony attended by Richard the Lionheart and Guy of Lusignan.
He married Adela (died 1185), daughter of Bouchard of Guise, and was the father of:
Abd al-Muttalib
Abd al- Muttalib Shaybah ibn Hashim( c. 497 – 578) was the grandfather of Islamic prophet Muhammad.
Baldwin of Avesnes
Baldwin of Avesnes( September 1219 in Oizy – 10 April 1295 in Avesnes) was a son of Bouchard IV of Avesnes and his wife, Margaret II of Flanders.
His parents' marriage was later declared illegal, because his father had already received minor orders.
Baldwin was later declared legitimate by the pope, at the instigation of King Louis IX of France.
In 1246, Baldwin received Beaumont as an apanage.
He fought his whole life, together with his brother John I, against his half- brothers from his mother's second marriage with William II of Dampierre.
He was said to be responsible for the accident that killed his half- brother William III of Dampierre during a tournament in Trazegnies.
After the Edict of Péronne and the death of his brother John, he reconciled with his mother, who sent him to Namur on a revenge expedition.
In 1287, Baldwin sold Dunkirk and Warneton to Guy, Count of Flanders.
He is also known as a chronicler; he wrote the" Chronique Universelle".
Charles Verlinden identifies the diplomat Baldwin of Hainaut as Baldwin of Avesnes.
William IV of Saint Omer
William IV of Saint Omer was the castellan of Saint- Omer from ca. 1171 until his death, as well as Lord of Beaurain and Fauquembergues.
The date of his birth is unknown; he is mentioned for the first time in 1157, when his uncle Walter was castellan.
William was the son of Walter's successor, William III of Saint Omer, and of a lady named Mathilda.
William IV is first attested as castellan in 1178, but according to Arthur Giry he may have succeeded his father already by 1171, as the genealogies of Baldwin of Avesnes imply that he was already castellan when married his wife, Ida of Avesnes( a sister of the Crusader James of Avesnes), and the couple's eldest son, the future William V of Saint Omer, was already over 15 years old in 1186.
William is attested in a series of documents and charters until 9 August 1190, but it appears that he then left for the Holy Land, where he died in 1191.
His wife, Ida of Avesnes, lived until sometime between 1205 and May 1211.
According to Baldwin of Avesnes, the couple had eleven children:

Question: Who is Bouchard Iv Of Avesnes's paternal grandfather?
Answer: Nicholas d'Oisy, Lord of Avesnes