BERLIN – The United Nations and many countries officially commemorate the Holocaust on Jan. 27, the anniversary of the liberation of Auschwitz. That place, where the Nazis perfected mechanized murder, has correctly become a universal symbol of the genocide of the Jewish people.

But the Holocaust did not begin at Auschwitz. Rather, 70 years ago, well before the gas chambers and crematoria were designed or constructed, the systematic murder of Europe’s Jews began as the German army swept through Poland, Ukraine and Belarus on its way eastward. Mobile killing units, frequently aided by regular soldiers and local collaborators, shot them where they lived and buried their bodies in hundreds of mass graves.

There they have remained, more than 1.5 million Holocaust victims, most in shallow graves unmarked and untended. Some of the sites are remote in forests or farmland, while others are in towns and villages. Entire communities were wiped out. The few Jews who by some miracle survived seldom returned, leaving no one to remember or care for the graves.

The Soviet Union tragically was not interested in taking note of the particular Jewish suffering during World War II. Communist propaganda maintained that all people of the USSR shouldered the same burdens.

So I should not have been surprised when on a visit a decade ago to my own family’s ancestral village, Smolyany, in eastern Belarus, I was shown the memorial erected in a nearby forest where the remaining Jews were shot and buried by the Nazis.

“On this site 800 Soviet citizens were murdered by German fascists,” the memorial read. “Do not forget.”

But who would know that these victims were Jews and that was why they were murdered? Who will know a generation from now?

At least this spot in Smolyany was undisturbed; that is not always the case. For more than 10 years Father Patrick Desbois, a French cleric from Paris, has been conducting, at his own initiative, investigations first in Ukraine and now in neighboring countries to find the mass graves of Holocaust victims. Elderly eyewitnesses have opened up to this soft-spoken Catholic priest and helped him identify hundreds of sites previously unknown where mass murders took place.

Many of these long-ignored sites have been exposed to the elements, to roaming animals and even to grave robbers. To appropriately honor these victims of the Holocaust, their graves must be identified, properly protected and memorialized.

A year ago AJC drew public attention to these mass graves. We brought to Berlin Father Desbois and like-minded individuals who were leading the identification efforts, who recognized the urgency of getting the work done before the last survivors and witnesses have passed, and who share a common call for action.

The concerted and comprehensive effort that we sought is now advancing with the establishment of an unprecedented, diverse international coalition, whose representatives gathered last week at AJC’s Berlin office.

The German government has provided funding for several initial pilot projects and to develop a long-term plan that includes a comprehensive list of sites. The data compiled by Father Desbois and his organization, Yahad in Unum, on hundreds of mass graves provides an invaluable beginning.

Indeed, members of our coalition visited five pilot memorial sites in Western Ukraine, north of Lviv, last month. Jewish partners in Ukraine are engaged in historical research so that appropriate memorial markers and informational plaques can be put in place.

The Committee for the Preservation of Jewish Cemeteries in Europe will provide rabbinic oversight, while the German War Graves Commission has offered its help and the voluntary assistance of German army cadets. Jewish community leadership in Poland and Belarus will enable us to extend the work to these countries as well.

There should be no illusions. This is a long-term, yet necessary, effort that will not be accomplished easily and perhaps never completely. But we are confident that with Germany’s support and the active engagement of the organizations and individuals that have joined our global coalition, we will succeed.

Seventy years later we shall properly honor the memory of these long-forgotten Holocaust victims. We shall ensure that their resting places are preserved and protected, and their lives are remembered.

Rabbi Andrew Baker is the American Jewish Committee’s director of international Jewish affairs.