The Nihang (also spelt as Nihung) or Akali (lit. "the immortals"), also known as Dal Khalsa, is an armed Sikh warrior order originating in the Indian subcontinent. Nihangs are believed to have originated either from Fateh Singh and the attire he wore or from the "Akali" (lit. Army of the Immortal) started by Guru Hargobind. Early Sikh military history was dominated by the Nihang, known for their victories where they were heavily outnumbered. Traditionally known for their bravery and ruthlessness in the battlefield, the Nihang once formed the irregular guerrilla squads of the armed forces of the Sikh Empire, the Sikh Khalsa Army.
The word Akali/akaali means timeless or immortal.
Literally, one who belongs to Akaal (beyond Time). In other words, an Akaali is that person who is subject of none but God only. Conceptually speaking, the terms Akaali, Khalsa and Sikh are synonymous. The term Akaali was first used during the time of Guru Gobind Singh Sahib. The term Akaali became popular in the last decades of the eighteenth century.
The term came to be associated with “commitment, fearlessness, boldness, struggle, and justice.”The word Nihang may come from the Persian word for a mythical sea creature (نهنگ). The term owes its origin to Mughal historians, who compared the ferocity of the Akali with that of crocodiles. The meaning of Akali in Sikhism however, is the immortal army of Akal (God).
According to Pashaura Singh and Louis E. Fenech, there exists three main theories regarding the genesis of the Nihangs. These three theories are summarized below:
Began with the son of Guru Gobind Singh, Fateh Singh with his blue clothing and turban with the Guru prescribing this uniform for his warriors.
Second hypothesis claims that they originate from the disguise of Guru Gobind Singh when he escaped from Chamkaur in 1704 or 1705.
Third theory postulates that they can be traced back to the garb of Akali Naina Singh of the Nishanwalia Misl.
Traditional Nihang dress is known as Khalsa Swarupa.