The killing of 1.5m Armenians by the Ottoman Turks during World War I remains one of the bloodiest and most contentious events of the 20th century, and has been called the first modern genocide.
In all, 25 concentration camps were set up in a systematic slaughter aimed at eradicating the Armenian people - classed as "vermin" by the Turks.
Winston Churchill described the massacres as an "administrative holocaust" and noted: "This crime was planned and executed for political reasons. The opportunity presented itself for clearing Turkish soil of a Christian race."
Chillingly, Adolf Hitler used the episode to justify the Nazi murder of six million Jews, saying in 1939: "Who, after all, speaks today of the annihilation of the Armenians?"
Yet, carried out under the cover of war, the Armenian genocide remains shrouded in mystery - not least because modern-day Turkey refuses to acknowledge the existence of its killing fields.
More on Mail Online, and ANI
Also see: Turkey recalls envoy to Sweden - Al Jazeera
and Turkey recalls Washington ambassador in genocide row - ABC