Khatshik Bakalian, a 73-year-old Lebanese Armenian, whose parents fled the mass killings of Armenians under the Ottoman Empire in 1915, points at a picture of his parents in the family album on April 17, 2015, in the historic town of Anjar, 37 miles east of Beirut in Lebanon's eastern Bekaa Valley. (JOSEPH EID/AFP/Getty Images)

It appears President Obama will not use the word "genocide" on Friday when acknowledging the massacres of perhaps more than 1 million Armenians living in the Ottoman Empire a century ago. That's when the nation of Armenia, as well as the far-flung Armenian diaspora, will mark the 100th anniversary of what they staunchly believe was a genocide.

There's little historical disagreement about the scale of the upheavals that began in April 1915 -- when Ottoman officials first ordered the removal of Armenian intellectuals in Istanbul, and later the mass deportation of ethnic Armenians mostly living in what's now eastern Turkey. But, as WorldViews discussed earlier, the question of how to remember it has been the subject of decades of debate and rancor, wrapped up in the the complex politics of the Cold War as well as the ironclad nationalism of a succession of Turkish governments.

It's the source of considerable international awkwardness. Obama isn't alone in his avoidance of the "g-word" -- he's joined by a host of other world leaders, including United Nations Secretary General Ban Ki-moon, as well as all his predecessors in the White House.

But there was a time when many in the international community were more certain of what took place. This is particularly true when it comes to the United States: Americans in the Ottoman Empire offered some of the first outsider testimonies of what transpired in 1915. Some U.S. officials even invoked the slaughter of the Armenians as moral justification for the United States eventually entering World War I against Germany and its allies.

To be sure, the unraveling of the Ottoman Empire between 1914 and 1922 saw mass violence and depravation visited on its non-Armenian populations as well. An estimated 5 million Ottoman civilians perished during the conflicts between this eight-year period.

The following accounts are from four Americans who witnessed what befell the Armenians of the crumbling Ottoman Empire. They are all taken from an excellent new book, "Great Catastrophe: Armenians and Turks in the Shadow of Genocide," by Thomas de Waal, an expert on the Caucasus and Black Sea region at the Carnegie Endowment for International Peace.

Henry Morgenthau, U.S. ambassador to the Ottoman Empire, in a cable sent to Secretary of State Robert Lansing on July 10, 1915:

Persecution of Armenians assuming unprecedented proportions. Reports from widely scattered districts indicate systematic attempts to uproot peaceful Armenian populations and through arbitrary arrests, terrible tortures, wholesale expulsions and deportations from one end of the Empire to the other accompanied by frequent instances of rape, pillage, and murder, turning into massacre, to bring destruction and destitution on them. These measures are not in response to popular or fanatical demand but are purely arbitrary and directed from Constantinople in the name of military necessity, often in districts where no military operations are likely to take place.

Morgenthau went on, explaining the shocking reasons behind the violence:

The Moslem and Armenian populations have been living in harmony but because Armenian volunteers, many of the Russian subjects, have joined Russian army in Caucasus and because some have been implicated in armed revolutionary movements and others have been helpful to Russians in their invasion... terrible vengeance is being taken. Most of the sufferers are innocent and loyal to the Ottoman government.

The execution of the Ottoman directives was uneven. In some areas, the bulk of Armenian men were able to leave their homes and towns. In others, wrote Henry Riggs, an American pastor in eastern Anatolia, "men very seldom left the province alive." According to some accounts, males over the age of 12 were systematically killed.

Riggs observed what happened to surviving women and children in the tragic deportation convoys marched out of Anatolia. They were waylaid by bands of Kurds and brutalized by the gendarmes, or soldiers, dispatched to guard them. Rape and abuse were rife.

Left with absolutely no protection, at the mercy of those brutal gendarmes, many of them criminals of the worst type, the women and children were driven along with such rigor that many perished from sheer exhaustion within the first few days. Of the treatment received by the younger and more vigorous women at the hands of men whose unbridled lust was no longer restrained by any fear of justice, no detailed account need be attempted. The fact of so many suicides at the [Euphrates] River is perhaps sufficient comment, though the women who escaped from other convoys and came to us for relief told of their own experiences of those nightly orgies in shocking detail.

Mary Gaffram, another American missionary, walked with a group of Armenians leaving the central Anatolian city of Sivas.

As far as the eye could see over the plain was this slow-moving line of ox carts. For hours there was not a drop of water on the road, and the sun poured down its very hottest. As we went on we began to see the dead from yesterday's company, and the weak began to fall by the way. The Kurds working in the fields made attacks continually, and we were half-distracted. I piled as many as I could on our wagons, and our pupils, both boys and girls, worked like heroes. One girl took a baby from its dead mother and carried it until evening. Another carried a dying woman until she died.

Jesse Jackson, the U.S. consul in Aleppo, sent this cable in September 1916 of what he witnessed by a town outside the Syrian city, where the last phase of the campaign was playing out.

The impression which this immense and dismal plain of Meskene leaves is sad and pitiable. Information obtained on the spot permits me to state that nearly 60,000 Armenians are buried there, carried off by hunger, by privations of all sorts, by intestinal diseases and typhus which is the result. As far as the eye can reach mounds are seen containing 200 to 300 corpses buried in the ground... women, children and old people belonging to different families.

Jackson described the surviving Armenians he encountered as "living fantoms."

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