Eric Christoffersen of Denmark
Eric Christoffersen (c. 1307 – c. 1332)  was king of Denmark from 1321 until his death, jointly with his father, King Christopher II.
He was a member of the House of Estridsen.
In Danish, he is sometimes called "Erik, elected king."
Eric was the eldest son of King Christopher II and Euphemia of Pomerania.
In 1321, he was elected king and crowned alongside his father as his junior co-ruler on 15 August 1324.
In 1325, his father asked him to halt the Counts of Holstein and their allies, but was deserted by his troops, taken prisoner and confined in Haderslev Castle.
His father was forced to abdicate and go into exile, while the 12-year-old Duke Valdemar of Southern Jutland was made king of Denmark under the regent, Count Gerhard III of Holstein.
After a period of chaos in the "magnates’ republic" of Denmark, King Christopher was restored as a puppet monarch in 1329 through the help of his half-brother Count John III.
Eric was released in 1330, on the condition he married Elizabeth of Holstein-Rendsburg, dowager duchess of Saxe-Lauenburg and sister of his father's enemy, Count Gerhard III, by whom he had no children.
The marriage was dissolved the next year as war again erupted between his father and Count John III and his brother-in-law Gerhard III.
He predeceased his father, fighting in the battles, which subsequently broke out between his father and Holstein.
On 30 November 1331, Eric was defeated at the battle at Danevirke, but managed to escape to Kiel, where he died of his battle wounds, a few months afterward, either in late 1331 or early 1332.
Eric was buried at Sorø Abbey, later his remains were transported to the St. Bendt's Church.
Upon his father's death in the same year, Denmark ceased being a formal kingdom, and for the next eight years it was subdued by various mortgagees to German military rule.
His younger brother would later regain Denmark from the Holsteiners and succeed as Valdemar IV of Denmark.
Francis of Denmark
Francis of Denmark( 15 July 1497 – 1 April 1511), was a prince of Denmark, Norway and Sweden, the youngest son of King John of Denmark and Christina of Saxony.
Princess Caroline-Mathilde of Denmark
Princess Caroline- Mathilde of Denmark( 27 April 1912 – 12 December 1995) was a daughter of Prince Harald of Denmark and granddaughter of King Frederick VIII of Denmark.
As the wife of Knud, Hereditary Prince of Denmark, she became Hereditary Princess of Denmark.
Eric III of Denmark
Eric III Lamb( – 27 August 1146) was the King of Denmark from 1137 until 1146.
He was the grandson of Eric I of Denmark and the nephew of Eric II of Denmark, whom he succeeded on the throne.
He abdicated in 1146, as the first and only Danish monarch to do so.
His succession led to a period of civil war between Sweyn III, Canute V, and Valdemar I.
Fred Le Deux
Frederick" Fred" Le Deux( born 4 December 1934) was an Australian rules footballer who played with Geelong in the Victorian Football League( VFL).
He is the grandfather of Tom Hawkins.
Agnes of Denmark
Agnes of Denmark( 1249 – after 1290) was the youngest daughter of Eric IV of Denmark and his wife Jutta of Saxony.
She was the official founder of the St. Agnes' Priory, Roskilde, becoming prioress there.
Henry Krause
Henry J." Red" Krause, Jr.( August 28, 1913 – February 20, 1987) was an American football offensive lineman in the National Football League for the Brooklyn Dodgers and the Washington Redskins.
He played college football at St. Louis University.
He is the grandfather of Jennifer Krause
He is the great grandfather of Payton Hoeing
Elizabeth of Holstein-Rendsburg
Elizabeth of Holstein- Rendsburg( c. 1300 – before 1340) was the regent of the Duchy of Saxe- Lauenburg during the minority of her son from 1321 until 1330.
She was by two consecutive marriages, duchess of Saxe- Lauenburg and queen of Denmark by marriage( 1330- 1331) to Eric Christoffersen, son of Christopher II of Denmark.
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.
Euphemia of Pomerania
Euphemia of Pomerania (1285 – 26 July 1330) was Queen of Denmark as the spouse of King Christopher II.
She was the daughter of Bogislaw IV, Duke of Pomerania, and his second spouse, Margarete of Rügen.
Euphemia wed Christopher in 1300.
The marriage was likely a politically arranged marriage to provide Christopher with political support from the dynasty of her mother as well as that of her father.
Not much is known about queen Euphemia.
Euphemia had at least six known children:
She is buried in the Sorø Abbey.

Question: Who is the maternal grandfather of Eric Christoffersen Of Denmark?
Answer: Bogislaw IV, Duke of Pomerania