Some quarters allege that LONG HAIR was a condition imposed by Singh Sabha in late 1880's.
Over sixteen decades earlier on 10th March 1716 paraded through the streets of Delhi were Banda Bahadur, 740 prisoners, and raised on bamboo poles were about two thousand heads
--"THE[IR] LONG HAIR STREAMING OVER THEM LIKE A VEIL" (William Irvine, Later Mughals, p.316.)
Long hair, as identity of the Sikhs was REITERATED, not introduced, by the Singh Sabha.
Maintaining unshorn hair was compulsory for every Sikh soldier, recruited by the East India Company.
by Harbans Singh - Baltimore, USA