Guru Nanak Dev - Guru Granth Sahib, as a collection of verses recorded in Gurmukhi. A Short biography of Guru Nanak Dev

Nanak was born on 15 April 1469 at Rāi Bhoi Kī Talvaṇḍī village (present-day Nankana Sahib, Punjab, Pakistan) in the Lahore province of the Delhi Sultanate, although according to one tradition, he was born in the Indian month of Kārtik or November, known as Kattak in Punjabi. Most janamsakhis (ਜਨਮਸਾਖੀ, 'birth stories'), or traditional biographies of Nanak, mention that he was born on the third day of the bright lunar fortnight, in the Baisakh month (April) of Samvat 1526.[8] These include the Puratan ('traditional' or 'ancient') janamsakhi, Miharban janamsakhi, Gyan-ratanavali by Bhai Mani Singh, and the Vilayat Vali janamsakhi.The Sikh records state that Nanak died on the 10th day of the Asauj month of Samvat 1596 (22 September 1539 CE), at the age of 70 years, 5 months, and 7 days. This further suggests that he was born in the month of Vaisakh (April), not Kattak (November). Kattak birthdate In as late as 1815, during the reign of Ranjit Singh, the festival commemorating Nanak's birthday was held in April at the place of his birth, known by then as Nankana Sahib.[9] However, the anniversary of Nanak's birth—the Gurpurab (gur + purab, 'celebration')—subsequently came to be celebrated on the full moon day of the Kattak month in November. The earliest record of such a celebration in Nankana Sahib is from 1868 CE. There may be several reasons for the adoption of the Kattak birthdate by the Sikh community. For one, it may have been the date of Nanak's enlightenment or "spiritual birth" in 1496, as suggested by the Dabestan-e Mazaheb. The only janamsakhi that supports the Kattak birth tradition is that of Bhai Bala. Bhai Bala is said to have obtained Nanak's horoscope from Nanak's uncle Lalu, according to which, Nanak was born on a date corresponding to 20 October 1469 CE. However, this janamsakhi was written by Handalis—a sect of Sikhs who followed a Sikh-convert known as Handal—attempting to depict the founder as superior to Nanak. According to a superstition prevailing in contemporary northern India, a child born in the Kattak month was believed to be weak and unlucky, hence why the work states that Nanak was born in that month. Bhai Gurdas, having written on a full-moon-day of the Kattak month several decades after Nanak's death, mentions that Nanak had "obtained omniscience" on the same day, and it was now the author's turn to "get divine light." According to Max Arthur Macauliffe (1909), a Hindu festival held in the 19th century on Kartik Purnima in Amritsar attracted a large number of Sikhs. The Sikh community leader Giani Sant Singh did not like this, thus starting a festival at the Sikh shrine of the Golden Temple on the same day, presenting it as the birth anniversary celebration of Guru Nanak. Macauliffe also notes that Vaisakh (March–April) already saw a number of important festivals—such as Holi, Rama Navami, and Vaisakhi—therefore people would be busy in agricultural activities after the harvest festival of Baisakhi. Therefore, holding Nanak's birth anniversary celebrations immediately after Vaisakhi would have resulted in thin attendance, and therefore, smaller donations for the Sikh shrines. On the other hand, by the Kattak full moon day, the major Hindu festival of Diwali was already over, and the peasants—who had surplus cash from crop sales—were able to donate generously.