What is Sikhism?
Sikhism is a monotheistic Indian religion founded by Gurū Nānak (1469–1539) in the Punjab in the late 15th century. It centers on three practices: interior repetition of the divine name (nām simraṇ), congregational singing of the gurūs' poetry (kīrtan), and selfless service (sevā). Its scripture, the Guru Granth Sāhib, has been the living teacher of the tradition since 1708, when the tenth gurū, Gurū Gobind Singh, closed the line of human gurūs and installed the text in that seat. Sikhism has roughly 25–30 million adherents, most of them in Punjab and the diaspora.
Is Sikhism a branch of Hinduism or Islam?
Sikhism is its own distinct tradition. Gurū Nānak emerged from the same northern Indian devotional environment as the medieval bhakti and Sant currents, and the Guru Granth Sāhib includes verses by Kabir and other Hindu and Muslim poets alongside those of the Sikh gurūs. But Sikhism has its own scripture, its own institutional history, and its own theology: a strict monotheism that explicitly rejects caste hierarchy and does not recognize the authority of the Vedas, the Quran, or any human teacher after the tenth gurū. It is not a reform of Hinduism, a variant of Islam, or a synthesis of the two.
What it claims
Sikhism's opening prayer is the Mūl Mantar, recited before every reading of the Guru Granth Sāhib: Ik Onkār, Sat Nām, Kartā Purakh, Nirbhau, Nirvair. One Reality, whose name is Truth, the maker who is also the doing, fearless, without enmity. This is a compressed doctrinal position: the divine is one, not many; it is recognizable rather than merely confessed; and that recognition removes the fear and enmity that follow from taking oneself to be a separate, threatened thing. The doctrinal weight falls on Ik (the One) and on Sat Nām (Truth as name), which together define both the object of worship and the means of approaching it. Interior name-repetition (nām simraṇ) and congregational singing (kīrtan) are the two disciplines the tradition treats as the operative practice. Everything else — ritual observance, dress code, communal infrastructure — is understood to support these or fall away. In perennialist readings, Sikhism has been described as Indian monotheism standing where the medieval Hindu Sant tradition and Sufi Islam met. The description is partial but not wrong.
The ten gurūs and the closed canon
The institutional shape of Sikhism since the early 18th century comes from a single decision by Gurū Gobind Singh (1666–1708): instead of naming a human successor, he transferred the gurū's authority to the scripture, the Ādi Granth, then renamed the Guru Granth Sāhib. The text has held that authority since. The Guru Granth Sāhib is an anthology, not a single author's work. It contains compositions of six of the ten gurūs alongside the bhagat bāṇī of medieval Hindu and Muslim poets: Kabir, Raidās, Nāmdev, Farīd, and roughly thirty others. At Vaisākhī 1699, Gurū Gobind Singh initiated the five original members of the Khālsā — the Pañj Pyāre — and established the five articles of faith known as the kakārs: uncut hair, comb, steel bracelet, knee-length undergarment, and ceremonial sword. The Khālsā is not the whole of Sikhism; many practitioners are not initiated. But it has been the visible institutional form of the tradition since 1699.
Where it sits in relation to its neighbours
Interior name-repetition (nām simraṇ) is structurally cognate with the *japa* of Hindu bhakti traditions, the Sufi *dhikr*, the *Jesus Prayer* of Eastern Christian hesychasm, and the mantra recitation the broader Indian yogic tradition carries. Congregational singing (kīrtan) is the same operation the bhakti traditions across India have developed, here in vernacular Punjabi rather than Sanskrit or Tamil. The communal kitchen (langar) — open to all regardless of caste, religion, or means — is the form *sevā* has taken as permanent institutional infrastructure. The Sikh Rahit Maryādā, adopted by the Shiromani Gurdwārā Parbandhak Committee in 1945, codifies what the tradition expects of practitioners. Outside that framework, the Sant Mat poetic substrate Sikhism shares with its Hindu and Muslim neighbours has continued to circulate in other forms — the Radhasoami movements and broader Sant lineages — though these are not Sikhism.
Why it isn't yet in the index
The English-language spiritual-media corpus this index draws from has very little Sikh material. No contemporary Sikh teacher in the corpus has the audio-book, podcast and lecture-circuit footprint that Hindu, Buddhist, and to a lesser degree Sufi teachers have built since the 1970s. The principal Sikh devotional medium — kīrtan performed in gurdwārās — does not travel well into the podcast-and-Audible economy that determines what the index can currently catalogue. The gap is documented here rather than papered over. The most accessible English-language entry points outside the index remain Khushwant Singh's A History of the Sikhs for institutional history, W. H. McLeod's scholarship for textual and doctrinal history, and the Guru Granth Sāhib itself in the Khalsa Consensus Translation. The recognition the Sant poetic substrate carries is not other than what the rest of the index's non-dual and mystical traditions describe. The local vocabulary differs and the institutional descent is its own, but the doors connect.