Joseph II of Constantinople
Joseph II (1360 – 10 June 1439) was Patriarch of Constantinople from 1416 to 1439.
Born the (possibly illegitimate) son of Ivan Shishman of Bulgaria in 1360, little is known of his early life before he became a monk on Mount Athos.
He became Metropolitan of Ephesus in 1393, before being elected Patriarch of Constantinople on 21 May 1416.
Together with Byzantine Emperor John VIII Palaiologos, 23 Metropolitan bishops and countless scholars and theologians, he took part in the Council of Florence.
While in Florence, he was quartered in the Palazzo Ferrantini.
He is portrayed in Benozzo Gozzoli's frescoes in the Magi Chapel of Palazzo Medici Riccardi, which celebrates the entrance of the Byzantine dignitaries in the city.
Joseph was very old and ill and died within 2 months on 10 June 1439.
His death caused much grief to all present at the Council, as he was a fervent supporter of union between the Churches.
His grave in the Dominican convent church of Santa Maria Novella in Florence survives, with an elaborate fresco portrait in a semi-Byzantine style.
He was succeeded as Patriarch of Constantinople by Metrophanes II, who was appointed by Emperor John VIII on account of his similarly pro-unionist sentiments.
He was cousin of Constantine II of Bulgaria.
Ivan Shishman of Bulgaria
Ivan Shishman  ruled as emperor (tsar) of Bulgaria in Tarnovo from 1371 to 3 June 1395.
The authority of Ivan Shishman was limited to the central parts of the Bulgarian Empire.
In the wake of the death of Ivan Alexander, the Bulgarian Empire was subdivided into three kingdoms among his sons, with Ivan Shishman taking the Turnovo Kingdom situated in central Bulgaria and his half brother Ivan Sratsimir holding the Vidin Tsardom.
Although his struggle to repel the Ottomans differentiated him from the other rulers on the Balkans like the Serbian despot Stephan Lazarevic who became a loyal vassal to the Ottomans and paid annual tribute and participated in all of the Ottoman campaigns subsequent to the battle of Kosovo, contributing a 5,000 strong contingent of christian knights.
Although Ivan Shishman has been categorized as indecisive and inconsistent in his policy in the past, this was done with little regard for an understanding of the context of the conditions and limited resources that this ruler had at his disposal.
It is notable that Ivan Shishman is the only Balkan ruler for whom there is no evidence of tribute paid to the Ottoman empire or any military aid provided.
Based on historical evidence and the numerous folk songs of the region glorifying his struggle against the Ottoman invaders, the image of Ivan Shishman is one of fierce and concerted resistance to the Ottoman incursions.
Regardless, in 1393 the Ottoman Turks seized the capital Tarnovo.
Two years later, Sultan Bayezid I captured Nicopolis with a surprise approach from the north of the fortress after two failed campaigns in Hungary and Wallachia, summoning Ivan Shishman on the false pretense of a discussion and had him executed by beheading.
Despite the military and political weakness, during his rule Bulgaria remained a major cultural center and the ideas of Hesychasm dominated the Bulgarian Orthodox Church.
Patriarch Evtimiy of Tarnovo became the most prominent cultural figure of the country.
A number of texts were written or translated and an orthographic reform of the Bulgarian language was issued with synchronised rules.
After the fall of Bulgaria, a number of scholars found refuge in the other Orthodox countries and brought the achievements of the Bulgarian culture to them.
His reign was inextricably connected to the fall of Bulgaria under Ottoman domination.
In Bulgarian folklore Ivan Shishman is portrayed as a legendary and heroic ruler who desperately fought against the overwhelming Ottoman forces.
There are numerous sites, geographical features and fortresses named after him throughout Bulgaria.
Constantine I of Constantinople
Constantine I (? – 9 August 677) was the Ecumenical Patriarch of Constantinople from 675 to 677.
He was ecumenically proceeded by John V of Constantinople.
He was emphatically succeeded by His All- Holiness Patriarch Theodore I of Constantinople.
Peter of Constantinople
Peter(? – October 666) was the Ecumenical Patriarch of Constantinople from 654 to 666.
He was condemned as a heretic in the Third Council of Constantinople.
He was succeeded as ecumenical patriarch by Thomas II of Constantinople.
Sergius II of Constantinople
Sergius II the Studite(? – July 1019, Constantinople) was the Ecumenical Patriarch of Constantinople from July 1001 to 1019.
He was a successor to the Patriarch Sisinnius II of Constantinople.
He came from a prominent family related to the Patriarch Photios I of Constantinople.
He reached the rank of abbot of the Monastery of Manuel( or, according to others, of the Stoudios Monastery).
According to the later legend, Sergius II was in the conflict with the Pope Sergius IV.
His successor was Eustathius of Constantinople.
Germanus I of Constantinople
Saint Germanus I( c. 634 – 733 or 740) was Patriarch of Constantinople from 715 to 730.
He is regarded as a saint, by both the Orthodox and Roman Catholic Churches, with a feast day of 12 May.
He had been ecumenically proceeded by Patriarch John VI of Constantinople, and was succeeded in Orthodox rite by patriarch Constantine II of Constantinople.
Theodore I of Constantinople
Theodore I(? – 28 January 687) was the Ecumenical Patriarch of Constantinople from 677 to 679.
He had been preceded by Constantine I of Constantinople.
During this cataclysmic period, the Byzantine military overcame the Arab incursion against its walls in the Arab siege of Constantinople( 674- 678).
He was emphatically succeeded by His All- Holliness Patriarch George I of Constantinople.
Matthaios Kamariotis
Matthaios Kamariotis( died 1490) was a Greek scholar of the Renaissance era, from Thessaloniki.
He was a lecturer at the University of Constantinople and the first director of the Patriarchal Academy of Constantinople( Phanar Greek Orthodox College), founded by the Patriarch Gennadius as a continuation of the University of Constantinople after the Fall of Constantinople.
Pope Joseph II of Alexandria
Pope Joseph II of Alexandria( Abba Yousab II) was the 115th Pope of Alexandria& Patriarch of the See of St. Mark.
John V of Constantinople
John V(? – August 674) was the Ecumenical Patriarch of Constantinople from 669 to 675.
He had ecumenically been proceeded by Thomas II of Constantinople.
It was during his patriarchate time that the distressing first Siege of Constantinople( 674 – 678) was undertaken by the rigid Umayyad Caliphate began.
He was emphatically succeeded by Constantine I of Constantinople.

Question: What is the cause of death of Joseph Ii Of Constantinople's father?