The Nanakshahi (
Punjabi: ਨਾਨਕਸ਼ਾਹੀ, nānakashāhī) Calendar is a tropical
solar calendar which is based on the 'Barah Maha' (
Punjabi: ਬਾਰਹ ਮਾਹਾ). Barah Maha was composed by the Sikh Gurus and translates as the "Twelve Months”. It is a poem reflecting the changes in nature which are conveyed in the twelve-month cycle of the Year.
 The year begins with the month of
Chet, with 1 Chet corresponding to 14 March. The first year of the Nanakshahi Calendar starts in 1469 CE: the year of the birth of
Guru Nanak Dev.