Analysis of information sources in references of the Wikipedia article "Singh" in English language version.
The use of the two names by baptized Sikhs was originally intended to end the prejudice created by names pertaining to the various Hindu castes
Singh was a common name utilised by Rajputs, the Hindu ruling or warrior caste.
The male members were given the surname Singh (lion) and female members were given the surname Kaur (princess), with the intention of creating a parallel system of aristocratic titles in relation to the Rajput hill chiefs of the surrounding areas of Anandpur.
As the term 'Singh' meaning 'lion' was adopted from the Rajputs, so too was the name 'Kaur'
The code of conduct (rahit) expected of all initiates of the Khalsa, as laid down by Guru Gobind Singh and subsequently eloborated, emphasises both the equality of its members and the martial spirit expected of them by awarding the Rajput titles of Singh ('lion') to men and Kaur ('princess') to women, irrespective of caste origin.
In the process of forming a casteless society, many first generation Nepalis (and Indians) changed their surnames to Singh, which is a neutral and now common surname.
Some individuals often drop their surnames and use generic names such as Kumar, Lal, Singh, or Chowdhary that are not jati specific.
Going by the usage, Singh is more a title than a surname, cutting across communities and religious groups.
In those days, "Singh" as a surname was very popular among a famous warrior caste of north India, the Rajputs. Some of the first Sikhs were also Rajputs.
Similarly, Koyeris, a backward caste, claim themselves as Kushwaha Kshatriya and Dusadh, another scheduled caste, claim themselves as Gahlout Kshatriya. Some of their members use titles like ' Singh ' and ' Thakur.