Peter I, Count of Saint-Pol
Peter of Luxembourg( 1390 – 31 August 1433) was a son of John of Luxembourg, Lord of Beauvoir, and his wife Marguerite of Enghien.
His inheritance included the counties of Brienne, Conversano and Saint- Pol.
John, Count of Saint-Pol
John of Saint- Pol( died 1344) was Count of Saint- Pol between 1317 and 1344.
He was the eldest son of Guy IV, Count of Saint- Pol and Marie of Brittany.
He married in 1319 with Joanna, daughter of John I of Fiennes, and had 2 children:
Beatrice of Luxembourg
Beatrice of Luxembourg( 1305 – 11 November 1319), was by birth member of the House of Luxembourg and by marriage Queen of Hungary.
She was the youngest child of Henry VII, Holy Roman Emperor and his wife, Margaret of Brabant.
Her two siblings were John of Luxembourg and Marie of Luxembourg, Queen of France.
Guy V, Count of Saint-Pol
Guy V of Châtillon, Count of Saint- Pol( d. 1360 in London) was a French nobleman.
He was a member of the House of Châtillon and was the son of Count John of Saint- Pol( d. 1344) and his wife Johanna of Fiennes.
In the Hundred Years' War, he served as a royal commander in the French army.
He fought several battles against the English in Picardy.
He was one of the hostages sent to England under the terms of the Treaty of Brétigny of 1360.
He died of the plague shortly after arriving in London.
Guy was married to Johanna( d. 1392), a daughter of Lord John I of Ligny.
Since they had no children, he was succeeded as Count of Saint- Pol by his sister Mahaut and her husband Guy of Luxembourg- Ligny.
Waleran III, Count of Ligny
Waleran III of Luxembourg( 1355 – 12 April 1415) Count of Ligny and Saint Pol, was a French nobleman and soldier.
Hugh IV, Count of Saint-Pol
Hugh IV of Saint- Pol( died March 1205 in Constantinople) from the House of Campdavaine, son of Anselm of Saint- Pol, was Count of Saint- Pol from 1174 to his death, and lord of Demotika( Didymoteicho) in Thrace in 1204 – 05.
He participated in the Third and Fourth Crusades.
Marie of Luxembourg, Countess of Vendôme
Marie of Luxembourg( died 1 April 1547) was a French princess, the elder daughter and principal heiress of Peter II of Luxembourg, Count of Saint- Pol and Soissons, and Margaret of Savoy, a daughter of Louis I, Duke of Savoy.
She belonged to the French, cadet branch of a dynasty which had reigned as Dukes of Luxembourg, and whose senior line provided several Holy Roman Emperors, before becoming extinct in 1437.
Her paternal grandparents were Louis of Luxembourg, Count of Saint- Pol and Brienne and Jeanne de Bar, Countess of Marle and Soissons.
Her maternal grandparents were Louis I, Duke of Savoy and Princess Anne of Cyprus.
Catherine of Luxembourg-Saint-Pol
Catherine of Luxembourg-Saint-Pol (died 1492), was a Duchess consort of Brittany, married to Arthur III, Duke of Brittany.
She was a daughter of Peter of Luxembourg, Count of Saint-Pol and Margherita del Balzo.
Catherine’s marriage to Arthur III took place on 2 July 1445.
In December 1445 she went to Nantes, where her husband organized wedding celebrations in her honor.
Then she lived in Parthenay and travelled only in 1457 with her husband again to Brittany, because his nephew, the duke Peter II, had fallen ill.
After Peter’s death (22 September 1457)
Arthur III became new Duke and therefore his wife Catherine briefly Duchess consort of Brittany, but Arthur already died on 26 December 1458 at Nantes at the age of 65 years.
His marriage with Catherine had remained childless.
Catherine lived as widow a secluded life, probably died in March 1492 and was buried in the Carthusian monastery of Nantes, which she had finished.
Joan, Countess of Ligny
Joan, Countess of Saint- Pol and Ligny( d. 18 September 1430, Avignon), called the Demoiselle de Luxembourg, was the daughter of Guy of Luxembourg, Count of Ligny and Mahaut of Châtillon, Countess of Saint- Pol.
At the death of Philip I, Duke of Brabant, she was his nearest living relative on the Saint- Pol side and inherited Saint- Pol and Ligny upon his death on 14 August 1430.
She was living at the time at Beaurevoir, which belonged to her favourite nephew John.
At this time, John held Joan of Arc, whom he had captured, as a prisoner.
The Demoiselle de Luxembourg showed kindness to her and pleaded with her nephew not to sell Joan to the English.
The Demoiselle died shortly thereafter; her fiefs were divided between her senior nephew, the Count of Brienne, who received Saint- Pol, and John, her favourite, who received Ligny.
The Demoiselle is a character in Philippa Gregory's 2011 historical novel" The Lady of the Rivers", which centres on her great- niece Jacquetta of Luxembourg.
Arthur III, Duke of Brittany
Arthur III , more commonly known as Arthur de Richemont (24 August 139326 December 1458), was briefly Duke of Brittany from 1457 until his death.
He is noted primarily, however, for his role as a leading military commander during the Hundred Years' War.
Although Richemont briefly sided with the English once, he otherwise remained firmly committed to the House of Valois.
He fought alongside Joan of Arc, and was appointed Constable of France.
His military and administrative reforms in the French state were an important factor in assuring the final defeat of the English in the Hundred Years' War.
The name Richemont reflects the fact that he inherited the English title of Earl of Richmond, which was held by previous dukes of Brittany, but his tenure was never recognized by the English crown.
At the very end of his life he became Duke of Brittany and Count of Montfort after inheriting those titles upon the death of his nephew Peter II.
Richemont had no legitimate issue and was succeeded in the duchy by his other nephew, Francis II.

Question: Which country Catherine Of Luxembourg-Saint-Pol's husband is from?
Answer: France