Gerard III, Count of Guelders
Gerard III of Guelders( 1185 – 22 October 1229) was the Count of Guelders and Zutphen from 1207 until his death in 1229.
He was a son of Count Otto I of Guelders, and is sometimes called Gerard IV or Gerard V.
He married Margaretha of Brabant, the daughter of Duke Hendrik I of Brabant, in 1206.
Catherine of Guelders
Catherine of Guelders( ca. 1440 – Guelders, January 25, 1497), was regent of the Duchy of Guelders between 1477 and 1492.
Catherine of Guelders was the fourth and youngest child of Arnold, Duke of Guelders( 1410- 1473) and Catherine of Cleves( 1417 – 1479).< br>
Until 1477, she led an inconspicuous life, in the shadow of her brother Adolf, at war with his father, and her sisters Mary, married to King James II of Scotland and Margaret, married to Frederick I, Count Palatine of Simmern .<br>
Despite efforts by her father, no suitable husband was found for Catherine .< br> 17th century theories that she was secretly married with Louis de Bourbon, Bishop of Liège, are now believed to be false.
Everything changed for Catherine in 1477, when Charles the Bold was killed in the Battle of Nancy.
Guelders had been under control of Charles the Bold since 1473, and now saw the chance to regain its independence.
As her brother Adolf was in Flanders, the States of Guelders convinced him to appoint his sister Catherine as regent, pending his return.
Catherine reluctantly agreed.
But the regency lasted much longer than expected because Adolf was killed in battle on June 27, 1477.
She then continued to rule as regent for his son Charles II, who was held with his sister Philippa by the Burgundians.
Catherine became involved in the Guelderian War of Independence with Maximilian of Austria.
In 1482, she was forced to conclude peace with Maximilian and to retire from politics.
In 1492, she witnessed the regained independence of Guelders under her nephew Charles II, Duke of Guelders .< br>
Catherine died in 1497 and was buried in the church of Geldern, where her grave can still be seen.
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.
Otto II, Count of Guelders
Otto II, Count of Guelders( Dutch: Otto II, Graaf van Gelre) was a nobleman from the 13th century.
He was the son of Gerard III, Count of Guelders and Margaretha of Brabant.
Reginald III, Duke of Guelders
Reginald III of Guelders( or" Renaud", known as" The Fat")( 13 May 1333 – 4 December 1371) was Duke of Guelders and Count of Zutphen from 1343 to 1361, and again in 1371.
He was the son of Reginald II of Guelders and of Eleanor of Woodstock, daughter of Edward II of England.
With the death of his father in 1343, his mother held the regency until 1344.
From 1350, his brother Edward asserted his rights and a quarrel of succession broke out between the two brothers until 1361.
Reginald was overcome in Tiel and was imprisoned in the castle of Nijenbeek.
There he became so large that he could not have left, even if the door had remained open—hence his appellation" The Fat".
Edward died on 24 August 1371, having been mortally wounded in the Battle of Baesweiler, and Reginald was released( according to the legend, the walls had to be cut away so he could leave); he held the ducal throne for only a short period, dying a few months later.
He was buried at Graefenthal Abbey.
As he did not have a legitimate child, the succession passed to his sisters: Mathilde( also, Machteld), who was married to John II, Count of Blois, and Maria, wife of William II of Jülich and mother to William I of Guelders and Jülich, on whose behalf she claimed the throne of Guelders.
The sisters and their respective followers( the" Heeckerens", from the party led by families of Van Heeckeren and their relatives, the Van Rechterens, supported Mathilde, while the faction known as the" Bronkhorsters" followed Maria) fought for the duchy of Guelders in the War of the Succession of Guelders.
Reginald II, Duke of Guelders
Reginald II of Guelders , called "the Black" (c. 1295 – 12 October 1343), was Count of Guelders, and from 1339 onwards Duke of Guelders, and Zutphen, in the Low Countries, from 1326 to 1343.
He was the son of Reginald I of Guelders and Marguerite of Flanders.
Maria, Duchess of Guelders
Marie of Guelders († May 12, 1405) was one of two pretenders to the title of Duchess of Guelders and Countess of Zutphen on behalf of her son during the War of the Guelderian Succession from 1371 to 1379.
The war began after the deaths of her brothers, Reginald III of Guelders and Edward of Guelders.
Edward died from wounds received at the Battle of Baesweiler, and Reginald, who was known as the fat, died months later.
Succession was also claimed by Marie's sister, Mathilda, whose side was called the "Heeckerens" and were led by Frederik van Heeckeren van der Eze (1320-1386).
Her party was called the "Bronckhorsters" and was led by Gijsbert V van Bronckhorst (1328-1356).
Upon victory of her party, the title of Duke of Guelders went to her son, William.
Marie was daughter of Reginald II, Duke of Guelders and Sophie Berthout, lady of Malines.
On December 25, 1362, she married William II, Duke of Jülich († 1393).
They had three children:
Otto I, Count of Guelders
Otto I of Guelders( 1150 – 1207) was a Count of Guelders and Zutphen from 1182 until his death in 1207.
He was a son of Duke Hendrik of Guelders and Agnes of Arnstein.
He married Richardis of Bavaria in 1184.
Richardis was a daughter of Otto I Wittelsbach, Duke of Bavaria.
Catherine of Cleves (1417–1479)
Catherine of Cleves (25 May 1417 – 10 February 1479) was Duchess of Guelders by marriage to Arnold, Duke of Guelders.
She acted as regent of Guelders during the absence of her spouse in 1450.
The Hours of Catherine of Cleves was commissioned for her.
Maarten van Rossum
Maarten van Rossum( c. 1478 – June 7, 1555) was a military tactician of the duchy of Guelders who became field marshal in the service of Charles, Duke of Guelders.
He was greatly feared outside his home country for the ruthless manner in which he waged war.
In a long career, he often put his motto Blaken en branden is het sieraad van de oorlogBurning and torching is the jewel of war") into practice.
His way of waging war was quite similar to that of his Italian colleagues, the condottieri, and was characterized by guerrilla- like tactics, in which the civilian population was spared even less than was usual in his time.
For thirty years he served the interests of the Dukes of Guelders in their struggle to safeguard the independence of the Duchy of Guelders against the Habsburg Netherlands of Charles V. Van Rossum had a number of military successes obtained through his use of ruses, daring and the indiscriminate destruction of civilian lives and property.
After the collapse of the Duchy of Guelders, he fought the last years of his life in the service of his old enemy Emperor Charles V against France.

Question: Who is Maria, Duchess Of Guelders's paternal grandfather?
Answer: Reginald I of Guelders