[East_Prussian]

From R.J. Rummel's Death By Government:

As the Red Army pounded the Wehrmacht back toward Germany's Eastern territories in October 1944, some 4,000,000 to 5,000,000 Germans fled or were forced by the Nazis to evacuate. The roads were clogged with millions of refugees, young and old, maim and sick, along with their carts and horses, and all sorts of belongings littered the roads; 500,000 of these refugees alone formed haphazard caravans across an ice covered lagoon to reach Baltic ports. Thousands were killed by Soviet artillery and strafing planes, machine gunned on the roads and run over by tanks, or disappeared into holes in the ice created by bombs. Thousands more that tried to escape on over crowded ships were killed when the ships were sunk by planes or submarines. Tens of thousands more died from exposure and sickness. Overall possibly 1,000,000 German civilians perished during this evacuation and flight, itself an incredible toll in human lives.
After the defeat of the Wehrmacht millions of Germans tried to return eastward to their former homes or areas. In the lands they passed through or returned to famine was widespread, social and health services were totally disrupted. Signs warned refugees that they would starve to death if they lingered.

Now Rummel's numbers (I hate using that term) are conservative, 15,000,000 deported of whom 1,863,000 were killed (this estimate being far too low). I recovered other information which puts the pre-expulsion population at 17,773,900 of whom 3,484,300 were killed (I can show a provence/region breakdown if anyone wishes), dying of rape (girls as young as 9), being tied to two trucks which were subsequently driven in opposite directions, old men and young boys who had their eyes gouged out before being shot...the list goes on and on....