The Indian Express has an excellent FAQ on the history of deras (Sikh sects) in Punjab:
•What are deras and why are they in the news?
A dera is technically the headquarters of a group of devotees who follow the teachings of a particular spiritual guru and generally have a living representative of the guru who is equally revered. The representatives of the gurus, who hold the gaddi, are normally anointed by their predecessors.
•How many deras are there in Punjab?
Estimates vary but it is generally believed that there are about 300 major deras across the state and the neighbouring state of Haryana. Out of these, about a dozen have substantial following — over one lakh devotees each. There are hundreds of others which are restricted to a few villages each.
•Are only Sikhs members of these deras?
No, membership of deras is not restricted to Sikhs. A number of Hindus are also members of these deras. In fact, some of the deras even have Muslim and Christian followers.
•Who are the main followers of the deras?
Although these deras generally have members from various castes and creeds, the majority of the members belong to the so-called “lower castes”, that is, members of Scheduled Castes and Backward Classes.
To read the full story click here.