Calendar reform the traditional fixed arithmetic Hebrew calendar, respectively. Calendar proposals that introduce a thirteenth month or change the Julian-Gregorian system of months often also propose new names for these months. New names have also been proposed for days out of the week cycle (e.g., 365th and leap) and weeks out of the month cycle. Proposals to change the traditional month and weekday names are less frequent. The Gregorian calendar obtains its names mostly from gods of historical religions (e.g., Thursday from Nordic Thor or March from Roman Mars) or leaders of vanished empires (July and August from the first Cæsars), or
Adoption of the Gregorian calendar calendar) and Myanmar (Burmese calendar), and other countries use a modified version of the Gregorian calendar, including Thailand (Thai solar calendar), Japan (Japanese calendar), North Korea (North Korean calendar) and Taiwan (Minguo calendar). While many religious organizations reckon their liturgical year by the Gregorian civil calendar, others have retained their own calendars. Alternative calendars are used in many regions of the world today to mark cycles of religious and astrological events. Use of different calendars had potential to cause confusion between contemporaries. For example, it is related that one of the contributory factors for Napoleon's victory at the Battle of