section_path: History
section_name: History
paragraph_text: History
  
  Sikhs have traditionally recognised two eras and luni-solar calendars: the Nanakshahi and Khalsa. Traditionally, both these calendars closely followed the Bikrami calendar with the Nanakshahi year beginning on Kattak Pooranmashi (full moon) and the Khalsa year commencing with Vaisakhi. The methods for calculating the beginning of the Khalsa era were based on the Bikrami calendar. The year length was also the same as the Bikrami solar year. According to Steel (2000), (since the calendar was based on the Bikrami), the calendar has twelve lunar months that are determined by the lunar phase, but thirteen months in leap years which occur every 2–3 years in the Bikrami calendar to sync the lunar calendar with its solar counterpart. Kay (2011) abbreviates the Khalsa Era as KE.
  
  References to the Nanakshahi Era have been made in historic documents. Banda Singh Bahadur adopted the Nanakshahi calendar in 1710 CE after his victory in Sirhind (12 May 1710 CE) according to which the year 1710 CE became Nanakshahi 241. However, Singh (2008) states the date of the victory as 14 May 1710 CE. According to Dilgeer (1997), Banda "continued adopting the months and the days of the months according to the Bikrami calendar". Banda Singh Bahadur also minted new coins also called Nanakshahi. Herrli (1993) states that "Banda is supposed to have dated his coins according to his new calendar. Although Banda may have proclaimed this era, it cannot be traced in contemporary documents and does not seem to have been actually used for dating". According to The Panjab Past and Present (1993), it is Gian Singh who "is the first to use Nanak Shahi Samvats along with those of Bikrami Samvats" in the Twarikh Guru Khalsa. According to Singha (1996), Gian Singh was a Punjabi author born in 1822. Gian Singh wrote the Twarikh Guru Khalsa in 1891.
  
  The revised Nanakshahi calendar was designed by Pal Singh Purewal to replace the Bikrami calendar. The epoch of this calendar is the birth of the first Sikh Guru, Nanak Dev in 1469 and the Nanakshahi year commences on 1 Chet. New Year's Day falls annually on what is 14 March in the Gregorian Western calendar. The start of each month is fixed. According to Kapel (2006), the solar accuracy of the Nanakshahi calendar is linked to the Gregorian civil calendar. This is because the Nanaskhahi calendar uses the tropical year instead of using the sidereal year which is used in the Bikrami calendar or the old Nanakshahi and Khalsa calendars.
  
  The amended Nanakshahi calendar was adopted in 1998 and released in 1999 by the Shiromani Gurdwara Prabhandak Committee ("SGPC") to determine the dates for important Sikh events. Due to controversy surrounding the amended calendar, it was shortly retracted. The calendar was re-released in 2003 by the SGPC with three dates: Guru Nanak Dev Ji's Birth, Holla Mohalla, and Bandi Chhor Divas kept movable as per the old Bikrami system as a compromise. The calendar was implemented during the SGPC presidency of Sikh scholar Prof. Kirpal Singh Badungar at Takhat Sri Damdama Sahib in the presence of Sikh leadership. The Mool Nanakshahi Calendar recognizes the adoption event, of 1999 CE, in the Sikh history when SGPC released the first calendar with permanently fixed dates in the Tropical Calendar. Therefore, the calculations of this calendar do not regress back from 1999 CE into the Bikrami era, and accurately fixes for all time in the future.