Vikram Samvat (Bikram Sambat, Vikram Samvat Vikram Samwat or Vikram's Era, Devanagari:विक्रम संवत्, abbreviated "V.S." or "B.S") is the calendar established by Indian emperor Vikramaditya. It is a popularly used calendar in India and the official calendar of Nepal.

The Vikrama Samvat was founded by the emperor Vikramaditya of Ujjain following his victory over the Sakas in 56 BCE, although it is popularly (and incorrectly) associated with the subsequent king Chandragupta Vikramaditya. It is a lunar calendar based on ancient Hindu tradition (see Hindu calendar and Vedic time keeping). The Vikram Samvat calendar is 56.7 years ahead (in count) of the solar Gregorian calendar. For example, the year 2056 BS began in CE 1999 and ended in CE 2000. In Northern India the calendar starts with the first day after the new moon in the month Chaitra, which usually falls in March/April in the Gregorian calendar. Again in Western India the same era begins with the first day after the new moon in the month of Kartika which usually falls in October and November in the Gregorian calendar. In Nepal, it begins in mid-April and marks the start of the solar new year. It is official calendar of Nepal.

Acharya Tulsi (October 20, 1914 – June 23, 1997) was a Jainist Acharya (an ascetic). He was the founder of the Anuvrata and the Jain Vishva Bharti Institute, Ladnun and the author of over one-hundred books. Dr. Radhakrishnan in his "Living with Purpose" included him in the world's 15 great persons. He was given the title "Yuga-Pradhan" in a function officiated by President V.V. Giri in 1971.

He was influential in the development of Acharya Mahapragya and Sadhvi Kanakprabha.

The son of devout Jain traders, Tulsi was born in 1914 in Ladnun, India to Jhumarmal Khatter and Vadana Ji. Acharya Kalugani, the family guru, greatly influenced Tulsi, later recalling: "His divine face fascinated my heart and I used to gaze at him for hours."

Tulsi took his monk's vows at age 11 with remarkable dedication, and by the time he was 16, he had already started attracting acolytes. In 1936, Kalugani nominated Tulsi to be his successor, making him head of Terapanth group. Through his oversight, he initiated more than 776 monks and nuns.