Rosh Chodesh Nissan
The beginning of the month of Nissan
Hebrew Calendar Date: The first of Nissan, the first month of the Jewish calendar, New Year for Kings.
When it began:
Nissan is the first month of the Jewish calendar according to the Torah.
On the first day of Nissan in the year 2448 from creation (1313 BCE), two weeks before the Exodus, God showed Moses the crescent new moon, instructing him regarding the setting of the Jewish calendar and the mitzvah of sanctifying the new month. “This month shall be for you the head of months, the first of the months of the year” (Exodus 12:2). This ushered in the first Jewish month, and commenced the Jewish lunar calendar that Jews have been following ever since, distinguishing Israel from other nations. It was the first mitzvah (commandment) given to the newly born nation of Israel, even before the exodus from Egypt.
The first of Nissan is also the New Year for the reigns of Jewish kings (in line with the national emphasis of the season).