Background
Grgur was the eldest son of Serbian Despot Đurađ Branković and Eirene Kantakouzene. In 1439, after the Ottomans captured Smederevo, the capital of the Serbian Despotate, they appointed Grgur as governor of his father estates captured by the Ottomans.
Career
Because he ploted against the Ottomans, they dismissed him and put him in prison in April 1441. In 1459 he retreated to Hilandar Monastery, took monastic vowes and monastic name German. On 16 October 1459 Grgur died in Hilandar.
He was the eldest son of Đurađ Branković and Eirene Kantakouzene.
After the Ottomans captured Smederevo in 1439, Grgur was allowed to govern his father"s former estates in southern Serbia, as Ottoman vassal. Đurađ had intention to mobilize forces to recover his lost territories of Serbian Despotate.
In April 1441 the Ottomans, probably justifiably, accused Grgur for treason and dismissed him from his governorship. Branković retreated to Hilandar where he took monastic vowes and monastic name German.
He soon died there on 16 October 1459.