During his tenure as Guru, Akali Nihang Guru Gobind
Singh decided to alter the infrastructure of the Akal Sena. He decreed
that all warriors of the Akal Sena should dress in blue
and wear a 'dumala' (a conical high sturdy turban).
However, in order to distinguish the higher-ranking
‘sidkhi’ (proven) Sikhs from less experienced
and newer warriors, they would display the 'farla'/'farrah'
(loose piece of hanging turban) on top of their dumala to represent
the Guru's battle standard.
Akali Nihang Singh Khalsa
An old painting of 3 Akali Nihang Singhs adorned with weapons and
'Farlas' at the top of their 'Dastaar Boongahs' (the towering sturdy
conical turban )
With this change, only they who had this farla would
be known as the Akalis - the very form of Maha Kal.
The lower-ranking warriors of the Akal Sena, though dressing like
the Akalis (with the exception of the farla), would be known as
'Nihang'. Thus the Akal Sena was divided into Akali
Nihangs and Nihangs.
Exactly when these changes happened cannot be dated
precisely but the earliest historical reference to Nihangs occurs
in the Dasam Guru Durbar.
When describing the battle known as ‘Hussaini
Yudh’ (which probably occurred between 1695 and 1698),
the 10th Guru mentions Nihangs being present on the battlefield:
'The Nihangs roared…
The Nihangs moved about the battlefield...
Martyred are the Nihangs.
They appear as if people intoxicated on cannabis.'
('Bachitter Natak', Dasam Guru Durbar)
An old artists impression of Akali Nihang Singh warriors engaged
This suggests that the Nihangs existed before the
creation of the Khalsa in 1699.