Hedwig Jagiellon, Electress of Brandenburg
Hedwig Jagiellon( 15 March
1513 – 7 February 1573) was a Polish princess, the daughter of Sigismund I the Old of Poland and Electress of Brandenburg by marriage to Joachim II Hector, Elector of Brandenburg.
Joachim Frederick of Brieg
Joachim Frederick of( Legnica) Brieg( 29 September
1550 – Brzeg, 25 March 1602), was a Duke of Oława and Wołów( since 1586 with his brother as a co-ruler until 1592) and Brzeg( since 1595) and Legnica( since 1596).
He was the eldest son of George II the Pious, Duke of Brzeg- Oława- Wołów, by his wife Barbara, daughter of Joachim II Hector, Elector of Brandenburg.
He was named after both grandfathers: Joachim II Hector and Frederick II of Legnica.
Paul Luther
Paul Luther (28 January 1533 – 8 March 1593) was a German physician, medical chemist, and alchemist.
He was the third son of the German Protestant Reformer Martin Luther and was successively physician to John Frederick II, Duke of Saxony; Joachim II Hector, Elector of Brandenburg; Augustus, Elector of Saxony and his successor Christian I, Elector of Saxony.
He taught alchemy to Anne of Denmark.
Barbara of Brandenburg, Duchess of Brieg
Barbara of Brandenburg( 10 August 1527 – Brzeg, 2 January 1595), was a German princess member of the House of Hohenzollern She was a Margravine of Brandenburg by birth and by marriage a Duchess of Brieg( Brzeg).
She was the second child but eldest daughter of Joachim II Hector, Elector of Brandenburg, by his first wife Magdalena, daughter of George, Duke of Saxony.
Hubba bint Hulail
Hubba bint Hulail was the grandmother of Hashim ibn' Abd Manaf, thus the great- great- great- grandmother of the Islamic" Nabī"( Prophet) Muhammad ibn Abdullah.
Elizabeth of Denmark, Electress of Brandenburg
Elizabeth of Denmark, Norway, and Sweden (24 June 1485 – 10 June 1555) was a Scandinavian princess who became Electress of Brandenburg as the spouse of Joachim I Nestor, Elector of Brandenburg.
She was the daughter of King Hans of Denmark, Norway and Sweden and his spouse, Christina of Saxony.
John George, Elector of Brandenburg
John George of Brandenburg( 11 September 1525 – 8 January 1598) was a Prince- elector of the Margraviate of Brandenburg( 1571 – 1598) and a Duke of Prussia.
A member of the House of Hohenzollern, he was the son of Joachim II Hector, Elector of Brandenburg, and his first wife Magdalena of Saxony.
Faced with large debts accumulated during the reign of his father, John George instituted a grain tax which drove part of the peasantry into dependence on a nobility that was exempt from taxation.
Though a staunch Lutheran opposed to the rise of Calvinism, he permitted the admission of Calvinist refugees from the wars in the Spanish Netherlands and France.
He was succeeded by his son Joachim Frederick.
Upon the death of his kinsman Albert I, Duke of Prussia in 1568, the Duchy of Prussia was inherited by the latter's underage son Albert Frederick.
John George's father was a co-inheritor of the Duchy of Prussia.
In 1577 the Brandenburg electors became co-regent with Duke Albert Frederick of Prussia.
Joachim II Hector, Elector of Brandenburg
Joachim II (or "Hektor"; 13 January 1505 – 3 January 1571) was a Prince-elector of the Margraviate of Brandenburg (1535–1571), the sixth member of the House of Hohenzollern.
Joachim II was the eldest son of Joachim I Nestor, Elector of Brandenburg and his wife Elizabeth of Denmark, Norway, and Sweden.
He received the cognomen Hector after the Trojan prince and warrior for his qualities and prowess.
John George of Ohlau
John George of Ohlau
( Polish: Jan Jerzy oławski)( 17 June
1552 – Ohlau( Oława), 6 July 1592), was a Duke of Ohlau and Wohlau Wołów( since 1586 with his brother as a co-ruler until 1592).
He was the second son of George II the Pious, Duke of Brieg- Ohlau- Wohlau( Brzeg- Oława- Wołów), by his wife Barbara, daughter of Joachim II Hector, Elector of Brandenburg.
Magdalena of Saxony
Magdalena of Saxony (7 March 1507 – 25 January 1534) was Margravine of Brandenburg, its "Electoral Princess", the Electoral equivalent of a crown princess.
She was the daughter of George "the Bearded", Duke of Saxony and his wife Barbara.
Magdalena's maternal grandparents were Kazimierz IV Jagiellon and his wife queen Elisabeth of Austria, daughter of Albert II of Germany.
She was a granddaughter of the Elisabeth aforementioned,mother of the Jagiellonians, queen of Poland, who had claimed the Duchy of Luxembourg in 1460s as being the younger daughter of the last Luxembourg heiress Elisabeth of Luxembourg, Queen of Bohemia.
Though by no means an heiress of her grandmother, she was intended to wed
the heir of her grandmother's older sister.
Joachim (1505–1571), the future elector of Brandenburg, was the eldest son and heir of their current claimant of Luxembourg, Joachim I, Elector of Brandenburg (1484–1535), the eldest son and heir of Margaret of Thuringia (1449–1501), Dowager Electress of Brandenburg, herself the eldest daughter and heiress of Anna, Duchess of Luxembourg and William of Saxony, Landgrave of Thuringia.
Magdalena was thus married, at Dresden, on 6 November 1524, to her second cousin's son Joachim Hector, the future Elector of Brandenburg.
Their son was John George, another future Elector of Brandenburg.
After Magdalena's death which occurred well before Joachim ascended the electorate, Joachim II Hector married Hedwig Jagiellon, daughter of King Sigismund I of Poland.

Question: Who is the maternal grandmother of Joachim Ii Hector, Elector Of Brandenburg?