Adoption of the Gregorian calendar for secular use occurred in Eastern Orthodox countries as late as the 20th century and some religious groups in some of these countries still use the "old style" (O.S.) Julian calendar for ecclesiastical purposes. The Kingdom of Bulgaria changed from the Julian to the Gregorian calendar during the First World War on 31 March 1916, where the next day was 14 April 1916. The Ottoman Empire's Rumi calendar, used for fiscal purposes, was realigned from a Julian to a Gregorian starting on 16 February/ 1 March 1917. The beginning of the year was reset to 1 January starting in 1918.
Jyeshtha (month) Jyeshtha (month) Jyeshtha or Jyēṣṭha (; "jēṭ"; "zeth") is a month of the Hindu calendar. In India's national civil calendar, Jyestha is the third month of the year. Known as "Joishtho" ( "Jyôishţhô") in Bengali, it is the second month of the Bengali calendar. In lunar religious calendars, Jyēṣṭha begins on the new moon and is the third month of the year. Traditionally, Jyēṣṭha is associated with high summer, and corresponds to May–June in the Gregorian calendar. In Tamil, the month is known as Aani, the third month of the solar calendar that begins in mid-June. In Vedic Jyotish, Jyēṣṭha