Nation Rosh Hashanah has begun: What to know about the two-day Jewish holiday that leads into Yom Kippur September 17, 2020September 18, 2020 Dwight Adams, Indianapolis Star Comments Off on Rosh Hashanah has begun: What to know about the two-day Jewish holiday that leads into Yom Kippur Rosh Hashanah, which begins on Friday and ends Sunday, kicks off the most important week of the year for Jewish people. Here's why it is so important.