Sectarian labels of Deoband and Barelvi are widely used today to uphold the Ahl al-Sunnah wa al-Jama'ah (the people of Sunna and the Majority Muslim Community) and cover a range of normative Sunni scholastic methodology, doctrine, jurisprudence and spirituality. Starting from this observation, sectarian labels radically challenge the origins of sectarian identities extended to Deoband and Barelvi traditions, which converge and diverge over a range of identities and beliefs yet belong to the Ahl al-Sunnah wa al-Jama'ah in Islam. Islamic studies scholars, social scientists, and others alike have widely covered foundational questions held by Deobandis and Barelvis, including the content of their beliefs and the boundaries between them. However, the origins of the sectarian identities of Deoband and Barelvi in Islam largely remain an open debate for historians, theologians, and political scientists. This paper will theorise the origins of Deoband and Barelvi's identity in Islam and its implications across time. Through an interdisciplinary approach of histography and reception history, this discussion will cover some of the main methodological, thematic and theoretical issues relating to the study of sectarianism, Deoband and Barelvi's political identities and the challenge in understanding what these labels mean in the larger field of Islamic studies and British Islam. Ultimately, the paper advocates for Deoband and Barelvi to foster intra-religious dialogue and promote Ahl al-Sunnah wa al-Jama'ah that recognises and celebrates unity as part of the Ahl al-Sunnah wa al-Jama'ah without reducing Deoband and Barelvi labels to predetermined templates of sectarian identity.