I have remarked elsewhere that IS' creation of Ajnad Media Foundation in summer 2013 with the production of a plethora of unique songs (e.g. 'Close ranks and pledge bay'ah [allegiance] to Baghdadi', 'My Ummah, Dawn Has Appeared/Loomed', and 'I am not content with a life of humiliation') helped to give the group a unique identity vis-a-vis other jihadi groups, particularly al-Qa'ida, from which, it was clear, what was then ISIS had de facto broken off following on from Baghdadi's refusal to disband ISIS. For example, the nasheed 'Close ranks and pledge bay'ah to Baghdadi', which emerged in September 2013, made reference to the forthcoming establishment of the Caliphate- something that was also emphasized in the emergence of the ISIS slogan 'The Promised Project of the Caliphate', in light of the group's takeover of Azaz in northern Syria bordering Turkey. Such have the Ajnad Media nasheeds become a marker of the group's distinct identity that ISIS' overtures to win over Somalia's al-Qa'ida affiliate ash-Shabaab were reportedly rebuffed with a sudden 180-degree turn-around by ash-Shabaab's leadership that even banned the broadcasting of ISIS nasheeds.
Though Ajnad Media productions can be readily identified as background music in IS videos, strengthening IS' claim to a unique identity, it turns out that in a recent video on media operations in 'Euphrates Province', IS has in fact appropriated without credit an old nasheed that has nothing to do with jihadism. The nasheed in question is called 'tamūju t-taḥāyā' ('the cheers surge') and first appeared in November 2009 in two versions by Saudi munshids: one of them 'Abu Zayad' Maher al-Wazab, and the other Muhammad al-Jabbari. The version used in the IS video is that of Muhammad al-Jabbari.
[Update: I suspect IS came to associate the nasheed with itself on account of IS fans posting the nasheed as a 'nasheed of the Dawla' on Youtube and other platforms: see e.g. here].
Here is a preliminary translation of the nasheed:
The cheers surge in the brilliance of the sky,
Like a brilliant necklace, great in purity.
For you have enlightened the meeting for us.
Oh cloud, renew and rise up with offering.
The bond of the brothers is capable of salvation.
For the sake of God do we increase membership.
And thus we live by connection like a crystal.
By it through regularity does the glory radiate.
When the light at dawn clothes us,
We become full moons, leading aside clarity [?].
And the allure of desires rushes away from us,
And slumbers far off in the surrounding of the sky.
So my companions and brothers, sing,
And strengthen the bond that we may preserve the comfort.
And commit to the pledge that we may harvest fruits,
And pick them from our source with the blessing of water.
Hearts are like the sculpture of clouds that have grown gradually.
And in their wake, the rain makes the waterskin flow.
So Lord, bless our meetings,
And increase them when we disembark on the shore of death.