This must be a representation of the Tatbir ceremony, where men work their heads with swords in memory of the death of Ali.

The painting seems to be called "10th of Muharram"

I understand it is by Fausto Zonaro (18 September 1854 – 19 July 1929) who was an Italian painter, best known for his Realist style paintings of life and history of the Ottoman Empire.

During his stay in Istanbul, Zonaro witnessed the Day of Ashura processions carried out by the Shia Muslims on the tenth of Muharram, and it was the procession of Tatbir that inspired him to paint his renowned painting 10th of Muharram, it was reported that Zonaro said "After witnessing the horripilating procession (of Tatbir) I wish I were able to meet this man they mourn for". The "man" Zonaro speaks of indicates to the oppressed grandson of the Muslim prophet Mohammed, Hussein ibn Ali.

The word "horripilating" was new to me, it seems to mean: hairs standing erect in a fierce emotional responce.