Joan, Countess of Chiny
Joan( c. 1205 – 17 January 1271) was the Countess of Chiny.
Joan was the daughter of Louis IV, Count of Chiny, and Matilda of Avesnes, and became ruler of the county upon her father ’s death on 7 October 1226.
She married Arnold IV, Count of Loon, son of Gerard III, Count of Rieneck, and Kunigunde von Zimmern, in 1228, whereupon he assumed the role of Count of Chiny.
Joan and Arnold had the following children:
She was succeeded as ruler of Chiny by her husband, Arnold II, Count of Chiny.
Reginar IV, Count of Mons
Reginar IV, Count of Mons (c. 950–1013) was the son of Reginar III, Count of Hainaut.
Lambert I of Leuven was his brother.
Lambert I, Count of Louvain
Lambert I of Louvain nicknamed" The Bearded"( born in Louvain, Duchy of Lotharingia, East Francia c. 950, died in Florennes, County of Namur, Duchy of Lower Lorraine, Holy Roman Empire on 12 September 1015) was the first Count of Louvain in 1003.
He was killed by Godfrey II, Duke of Lower Lorraine in battle for Godfrey's claim of Count of Verdun.
He was the son of Reginar III, Count of Hainaut and Adela d' Eguisheim, daughter of Hugh V, Count of Eguisheim.
His brother was Reginar IV, Count of Mons.
He was the husband of Gerberga of Lower Lorraine, and father of:
Werner, Count of Valenciennes
Werner( Garnier, Warin)( died 973), Count of Valenciennes and Count of Hesbaye and Zülpich, brother of Renaud, Count of Mons.
His parentage is unknown.
In 953, Reginar III was defeated by King Lothair and Archbishop Bruno, and banished to Bavaria.
At that time, Werner became the successor of Rudolf as Count of Hesbaye, Werner, is referred to as count in a charter confirmed by Bruno.
Before 966, it appears that at least some of Rudolf's property was confiscated and placed under Werner.
After the disgrace of Count Reginar III, Godfrey I, Duke of Lower Lorraine, received the County of Hainaut, which included the cities of Mons and Valenciennes.
After the death of Godfrey, Amaury became Count of Valenciennes, while Richer assumed the countship of Mons.
After the death of Amaury, Emperor Otto I appointed Werner as the Count of Valenciennes.
Returning from exile in 973, the sons of Reginar III, Reginar IV, Count of Mons, and Lambert I, Count of Louvain, killed both Werner and his brother Renaud at the battle of Peronne.
Werner had no known children.
Reginar III, Count of Hainaut
Reginar III (c. 920 – 973) was a Count of Hainaut from approximately 940 until his exile in 958.
He was the son of Reginar II, Count of Hainaut.
He took part in the rebellion of his uncle Gilbert, Duke of Lorraine.
When Gilbert was killed in 939, Regnier had to pledge fealty to King Otto the Great.
He then allied himself with King Louis IV of France, but King Otto sent duke Hermann of Swabia to quell the rebels in 944.
Otto appointed Conrad the Red as duke of Lotharingia, who tried to diminish the power of Reginar.
However, when Conrad rose against Otto, Reginar supported him.
In an anarchic situation, Reginar appropriated the dowry of Gerberga of Saxony, Otto's sister and mother of the French king, and also church property.
In 953, Bruno, Archbishop of Cologne, who had also been appointed duke of Lotharingia, restored order and defeated Reginar.
As Reginar refused to submit, he was exiled to Bohemia, where he died.
Baldwin II, Count of Hainaut
Baldwin II of Mons( 1056–1098?) was count of Hainaut from 1071 to his death.
He was the younger son of Baldwin VI, Count of Flanders and Richilde, Countess of Mons and Hainaut.
Manasses de Ramerupt
Manasses( died after 4 February 1031), son of Hilduin III, Count of Montdidier.
He was often mistaken for his uncle Manasses, Count of Dammartin.
Manasses married Beatrix of Hainaut, daughter of Reginar IV, Count of Mons, and Hedwig, daughter of Hugh Capet, widow of Ebles I, Count of Roucy.
They had three children:
No further information could be found on the descendants of Manasses.
Reginar V, Count of Mons
Reginar V( c. 995–1039), Count of Mons, was the eldest son of Reginar IV, Count of Mons and Hedwig of France.
His maternal grandparents were Hugh Capet of France and Adelaide of Aquitaine.
Herman, Count of Hainaut
Herman (died 3 July 1049), Count of Mons and Hainaut, son of Reginar V, Count of Mons, and Mathilde of Verdun, daughter of Herman, Count of Verdun.
As the Count of Mons, a title inherited from his father, he allied with Godfrey the Bearded, Duke of Lorraine, and Baldwin V, Count of Flanders, against Emperor Henry III.
This won the countship of Valenciennes, completing the reconstruction of Hainaut.
His wife, who preferred an alliance with the emperor, attempted to get Herman to imprison Wazo, Bishop of Liège, but he refused.
In 1040, Herman married Richilde, whose origins are uncertain.
Herman and Richilde had two children:
After the death of Herman, Richilde married the son of Baldwin V, who arranged for Herman's children to be disinherited.
Richilde's new husband, Baldwin VI the Good, became Herman's successor and count of a unified Hainaut/Flanders.
Because of this passage of Hainaut to her new husband and children, Richilde is sometimes wrongly portrayed as daughter of Reginar V.
Her true parentage is subject to speculation, one theory being that she was the daughter of a count of Eguisheim and Dagsbourg.
Ebles I of Roucy
Ebles I of Roucy( died 11 May 1033) was count of Roucy from 1000 to 1033 and archbishop of Reims from 1021 to 1033.
His father has traditionally been considered to have been Giselbert, Count of Roucy and Reims.
A by Jean- Noël Mathieu resolves some inconsistencies by instead placing Giselbert as his matrilineal great uncle, and Eble de Poitiers as his father.
He married Beatrix, the daughter of Reginar IV, Count of Mons and Hedwig of France( daughter of Hugh Capet).

Question: Who is Reginar Iv, Count Of Mons's paternal grandfather?
Answer: Reginar II, Count of Hainaut