Sikh historian Harjot Singh Oberoi argues that, despite the historical linkages between Sikhs and Punjab, territory has never been a major element of Sikh self-definition. He makes the case that the attachment of Punjab with Sikhism is a recent phenomenon, stemming from the 1940s. Historically, Sikhism has been pan-Indian, with the Guru Granth Sahib (the main scripture of Sikhism) drawing from works of saints in both North and South India, while several major seats in Sikhism (e.g. Nankana Sahib in Pakistan, Takht Sri Patna Sahib in Bihar, and Hazur Sahib in Maharashtra) are located outside of Punjab.