Human Migration

Under Construction

Prehistory:

Earliest know ancestor in the bipedal, upright, hominid family (see taxonomy) is Orrorin Tugenensis, which lived about 6 M years ago in Africa.

Pierolapithecus Catalaunicus (13 M B.C.) is discovered in Spain.
  It is believed by some to be the link between early humans and the apes
  (gorillas, orangutans and chimpanzees families.)
Orrorin Tugenensis  (6 M B.C.) at Tugen Hills, Kenya
   Earliest known bipedal, upright, hominid 
Ardipithecus ramidus (5-4.3 M B.C.) Ethiopia
Australopithecus Anamensis (4.2-3.9 million B.C.) Kanapoi, Kenya.
Australopithecus Afarenis (3.9-3 million B.C.) occupied Eastern Africa.
Australopithecus Africanus (3-2.3 million B.C.) occupied Taung Southern Africa
Australopithecus Aethiopicus (2.8 M-2.3M B.C.) is discovered in Omo Basin, Ethiopia.
Homo Habilis (2.5-1.6 million B.C.) occupied Eastern and Southern Africa.  
Homo Rudolfensis (2.4M-1.8 M B.C.) is discovered Koobi, Kenya.
Australopithecus Boisei (2.3-1.4 M B.C.) is discovered in Olduvai, Tanzania
Australopithecus Robustus (2-1.2 million B.C.) occupied Southern Africa. 
  
Homo Ergaster (1.8-1.4 million B.C.) occupied Eastern Africa.
Homo Dmanisi (1.8 M B.C.) man discovered in Dmanisi, Georgia
Homo Erectus (1.6 M B.C.)  is believed to have evolved into a separate species 
in Java, Indonesia.  Remains are verified in Java and Turkana, Kenya.
1,000,000 B.C. Some people suggest Homo Erectus is differentiated between 
  Homo Erectus African and Homo Erectus Asian about this period.
  Others suggest they evolved from separate species. 
900,000 B.C.  - Growing evidence suggests Homo Erectus (Ceprano) likely roamed 
  Italy, Germany, Spain and Britain about this time.
800,000 B.C.  Homo Erectus Stone tools are discovered in southern China.
500,000 B.C.  Pithecanthropus (Homo Erectus), using the hand-axe, in
   Indonesia, China, Africa, and Europe.
400,000 B.C. Homo Neanderthals of Schoningen, Germany are using precisely designed
  throwing spears. 
270,000 B.C. Homo sapiens (archaic) Analysis of mans Y chromosome suggests
  homo sapiens (modern man as opposed to modern homo sapiens) originated about this time.
250,000 B.C. Stone tools are being used in England. 
150,000 - There is some circumstantial evidence of migration from Australia to China.
200-50,000 B.C. Evolution of Modern Homo sapiens
59,000 B.C. Some genetic theorists believe modern man emigrated from Africa about this time
      and dispersed around the world by 50,000 B.C. based on the X chromosome. 
60-40,000 B.C. - Australia
30-23,000 B.C. Cro-Magnon (France)  
20-15,000 B.C. N. America The DNA studies suggests America is populated 18,000 to 13,000 B.C.
     which is not supported by the hard facts that supports a much earlier population.

As of 2006 there were still two leading contradictory models, around since the early 1980's, that attempt to explain modern human evolution:

The replacement model (Lucy theory)
Proposes that modern humans evolved from archaic Homo sapiens 200,000-150,000 years ago only in Africa and then some of them migrated into the rest of the Old World replacing all of the Neandertals and other late archaic Homo sapiens beginning around 100,000 years ago.
The regional continuity (or multiregional evolution) model.
Proposes that modern humans evolved more or less simultaneously in all major regions of the Old World from local archaic Homo sapiens.

Source:Handprint : Ancestral Lines