Why this day?
Jewish history is long and filled with many stories of slavery and freedom, sorrow and joy, persecution and redemption. For Jews, their history, their family, and their relationship with God have shaped their religion and their identity. The Hebrew calendar is filled with varied holidays that incorporate and reiterate the history and tradition of the Jewish people.
After the horrors of the Holocaust, Jews wanted a day to memorialize this tragedy. But what day? The Holocaust spanned years with suffering and death spread throughout these years of terror. No one day stood out as representative of this destruction.
So various days were suggested.
The tenth of Tevet was proffered. This day is Asarah B'Tevet and marks the beginning of the siege of Jerusalem. But this day holds no direct relation or tie to the Holocaust.
The Zionists in Israel, many of whom had fought in the ghettos or as partisans, wanted to commemorate the beginning of the Warsaw Ghetto uprising - April 19, 1943. But this date on the Hebrew calendar is the 15th of Nissan - the beginning of Passover, a very important and happy holiday. Orthodox Jews objected to this date.
For two years, the date was debated. Finally, in 1950, compromises and bargaining began. The 27th of Nissan was chosen, which falls beyond Passover but within the time span of the Warsaw Ghetto uprising. Orthodox Jews still did not like this date because it was a day of mourning within the traditionally happy month of Nissan. As a final effort to compromise, it was decided that if the 27th of Nissan would affect Shabbat (fall on Friday or Saturday), then it would be moved. If the 27th of Nissan falls on a Friday, Holocaust Remembrance Day is moved to the preceding Thursday. If the 27th of Nissan falls on a Sunday, then Holocaust Remembrance Day is moved to the following Monday.
On April 12, 1951, the Knesset (Israel's parliament) proclaimed Yom Hashoah U'Mered HaGetaot (Holocaust and Ghetto Revolt Remembrance Day) to be the 27th of Nissan. The name later became known as Yom Hashoah Ve Hagevurah (Devastation and Heroism Day) and even later simplified to Yom Hashoah.
This year, the Yom Hashoah will be on May 1, 2008.