His origin and ancestry is uncertain; historians Mór Wertner and Pál Engel assigned him to the Hont-Pázmány clan as the son of Jakó Hont-Pázmány from the Födémes branch,[1] while Attila Zsoldos argued it is also considerable that Palatine Mog was identical with Mog from the gens Csanád whose son Michael is mentioned by a charter in 1237.
The pope instructed John, Archbishop of Esztergom and Katapán, Bishop of Eger to investigate the case and then carry out the invalidation in June 1206.
Duke Andrew hatched his umpteenth conspiracy against his elder brother Emeric, King of Hungary with the help of many other prelates and lords, including Palatine Mog.
According to the letter of Emeric to Pope Innocent III, Mog's betrayal encouraged Andrew to rebel against his rule and make an attempt to gain the throne.
[14] Mog lost all of his political influence at the royal court during the remaining rest of Emeric's reign, and in this desperate situation, he decided to fulfill his vow finally thus he joined to the Fourth Crusade.
It is possible he traveled to the Holy Land in the accompaniment of the French knights of Simon de Montfort, who stayed in the Republic of Venice then marched to Acre via Apulia.
[15] He returned to Hungary when Andrew II ascended the throne in 1205, following the sudden death of his nephew Ladislaus III, Emeric's son.
[16] Mog participated in Andrew's campaign to recapture Galicia and protect the realm of the child-prince Daniel Romanovich in the late autumn of 1205.
When Andrew, now also "King of Galicia and Lodomeria" returned to home, he left behind a Hungarian garrison in Sanok under the leadership of Mog in early 1206.