Walaashay, calm down. There is no evidence that it originated with Somalis or with any one particular group of East Cushites. All we know is that it seemingly was the pre-Islamic faith of many or even most East Cushites and I think possibly also South Cushites to some extent. In fact, I remember reading that there was evidence of the word "Waaq" itself being a very, very early loan from Nilo-Saharan back when our ancestors still lived in Sudan over 5,000 years ago:
So this religion is very old among Cushites in general and some of its roots may go back to the Proto-Cushites. Somalis have no real unique claim to it. Many traditions from Waaqism also still remained within Muslim Somali and Afar culture until just recently, for the record. Customs like trial by fire, a belief in sacred trees and congregating around them and belief in semi dieties like "Huur" and "Nidaar" as well as Somalis' inclination toward Sufism and the belief in saints is very similar to the "Qallu" concept in Waaqism where a priest is considered something of a very special person inhabited by good spirits (Ayaanle in Somali/Ayanas in Oromo) who's curses were to be feared and blessings were to come true:
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What's fascinating is that some of these customs and beliefs even entered the qabiil origin stories. Sheikh Darood's story is a very prime example. In the original story, from what I recall, he appears at the top of a great tree and asks the local people to bring him a
woman among them to wed so that he may descend and guide them. This is flat-out a Waqist story that repeats itself across the Horn among Afars and Oromos as well:
Belief in the Sky-God may relate to the myth of the man who was sitting in a tree (perhaps a sacred tree, even an olive). This is a common myth of origin told by Cushitic people of the Horn, particularly the Oromo, Afar, Saho and Somali (Luling 1988). According to this myth, a little girl discovered a stranger from the sky, a man, sitting on a tree, who would only agree to come down when he was promised that he could marry the local girl who found him. He was allowed to marry her, and the people emerged from their union. Versions of this myth are widespread in the Horn. It seems to indicate a potential link between the notion of trees and ancestral figures, as also exemplified by Konso waga sculptures. As an example, the wagar is, as noted earlier, carved from the wood of a sacred tree. The sycamore tree is, similarly, venerated by Cushitic peoples (Burton 1966; Trimingham 1965, p. 260; cf. Hallpike 1972). More broadly, it can be said that the worship of trees is extremely important within many Cushitic-speaking societies of the Horn even today, including the Konso and Oromo. Thus, the worship of trees and its potential link with the wagar are relevant to discussions of Sky-God belief. The potential link is the sacred fertility that the wagar is considered to provide. An investigation of the relationship between the idea of sacred trees, the myth of a man in a tree, and the wagar may suggest something of the deeper nature of Waaq. - Wagar, Fertility and Phallic Stelae: Cushitic Sky-God Belief and the Site of Saint Aw-Barkhadle, Somaliland, by Sada Mire
A little hilarious to think that people like Sheikh Darood, who are commonly associated with the Islamization of Somalis, have pre-Islamic elements woven into their stories. Shows you how syncretic the adoption of Islam was among Somalis.
But anyway, it is every bit their religion as it was ours once upon a time.