The article examines the introduction of the Nanakshahi calendar in 1998 (amended in 2003) as an attempt to unify the Sikh community and shape the Sikh identity. The evolution of the Sikh community is a long process resulting from combining different trends. The Sikh community started as a sect in Hinduism in the time of Guru Nanak (1469–1539) but developed as a new religion under the leadership of his successors, all of whom are known as the Gurus. The dates of the main historical events of the Sikhs, along with agricultural and New Year celebrations (Diwali, Holi), became the main festivals of the Sikh year. Gurpurbs, or memorial days of the Sikh Gurus, are also essential to the Sikh religious year. The existence of a significant portion of Sikhs in the diaspora further complicates this process and preserves alternative versions of Sikh identity. Religious authorities introduced the Nanakshahi calendar to bring uniformity and unanimity to Sikhs and create religious boundaries between the Sikhs and the Hindus. In 2003, this calendar was put into action. However, some Sikh holidays are still celebrated in the old manner according to the old Vikram (Bikrami) North Indian calendar. Sikh communities are now divided over the Nanakshahi calendar and Sikh gurus’ memorial days, the Gurpurbs.