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At the time loyalties were personal/feudal and not ethnic in an 19th-century style. Just because a state is run in one language does not mean anybody else uses it or identifies as such. E.g. England was run in French and Latin for centuries and nobody considers the often monolingual-French successors of William to be anything other than English.
National identities simply did not apply at the time. Not that I'd object to Saladin being an Arab, but how would you qualify the Persian-speaking Turks who ruled Arab lands at the time, including the Bahri and Burji Mamluks that came after the Ayyubids?
Also, my question from 20 years ago still stands: what do the Kurds say?
Persianized Turks, Turks in ancestry, but Persian in culture and customs, Mamluks were Circassian, Turk and Georgian in ancestry, but Arab in culture.
Rawadiyya were Kurd in culture, but Arab in ancestry. So the Arab claim to Ayyubid which has always existed isn't dumbfounded. It has solid grounds. It's only with advent of Western scholarship that Salaheddin ancestry has been ignored and Ayyubids written letters of them denouncing being Kurdish in ancestry or their genealogies to Azd being denounced as ''claiming prestige'' , but that was an error on their part. Western scholars thought since medieval sources said they were part of Hadhbani Kurds that they were originally of them, but that was an error, they merely intermarried them and associated with them through marrriage ( which is common in the Muslim world and tribal sphere)
Many Ayyubid Kings never claimed to be Kurds through ethnicity , rather through marriage only.
You now have Kurds trying to say Rawaddiya were full Kurds which is laughable and can never be done, because even the Emir of Rawadiyya, Wahsuddan was praised by Poet Qatran Tabrizi who lived during that time for his Arab ancestry.
This is the poem:
در مدح ابومنصور وهسودان بن مملان In Praise of Abu Mansur Wahsudan ibn Mamlan
ز بهر آنکه نسب زی عجم کند سوی ام
ز بهر آنکه گهر زی عرب کشد سوی اب
Because his lineage through his mother goes to the Ajam
Because his noble essence through his father goes to the Arabs
Furthermore check the following book on the history of Kurds.
In this book A MODERN HISTORY OF THE KURDS scholar admits the tribe the Ayyubidd claim descent from ''Rawaddiya'' were Kurdified Arabs” “ was considered to be Kurdish within 200 years” although its Arab origin was well known.
And for anyone claiming the poem about Abu Mansur Wahsudan the Emir of Rawaddiya in the 11th century is fake check this.