Who were Gündoğdu Bey & Sungurtekin Bey?

The narrative in relation to Gündoğdu Bey and Sungurtekin Bey is that they didn’t support Ertuğrul’s decision to go west towards the Eastern Roman/Byzantine borders, and this is dramatised in Season 2 of Diriliş: Ertuğrul.

We know next to little of them both. In comparison to their brothers, we have no idea of when they were possibly born and died and nor is it speculated; we also don't know where they are buried, and nor is it clear if they indeed married/to whom did they marry. In Resurrection: Ertugrul, Gundogdu is shown to have a wife by the name of Selcan Hatun (see below) and from her had two children who were mentioned in Season 5: Suleyman Alp and İltekin Alp.

In addition, it is not clear if Gundogdu Bey’s mother was in fact Hayme Ana with some narratives suggesting that Haymana was the second wife of Suleyman Shah (Gunduz Alp), and this is also alluded to in Dirilis Ertugrul (Season 2) with the character of Gündoğdu mentioning being a step-son.

Both though were said to have lived pretty unremarkable and quiet lives with apparently only verbal accounts being told about them by people through the generations.

Hence, they over time faded away in history with some speculating that the reason was because they were looked at as not making the right decision in comparison to their younger brothers and consequently weren’t really “paid attention to.”

It was also said they suffered big losses during a great Mongol invasion and they thereafter lived subserviently under Mongol rule.

Moreover, in the aforementioned Season 2 of Resurrection Ertugrul, Sungur Tekin is shown to be a spy of the Sultan of the Anatolian Seljuk Sultanate of Rûm: Alâeddin Keykûbad. Resurrection: Ertugrul further narrates that he was captured by the Mongols and served the founder and 1st Great Khan (Khagan) of the Mongol Empire, Genghiz Khan/Chingis Khan, and thereafter his son & successor, and 2nd Great Khan, Ogedei Khan. Sungur apparently used this opportunity to provide information about the Mongols to the Seljuks.

Considering that it was mentioned above that we know next to nothing about Sungurtekin or Gundodgu (and neither is there any Mongol account of such a thing occurring), it is easy to conclude that this was pure dramatisation and done for the sake of the series rather than based on anything historical.

Lastly, both characters returned in the series after the tribe split (Season 2) with both Gundogdu and Sungurtekin arriving at Ertugrul’s tribe on separate occasions. This again though may have been pure dramatisation and done for the sake of the series.