The Ainu (pronounced: [?ajnu], which means "people/person" in the language of Ainu), were natives of northern Honshu, Hokkaido, parts of Sakhalin (peacefully shared with the Nivkh natives), Kuril islands, and parts of Kamchatka penninsula. Ainus in Kuril and Sakhalin islands were relocated to other parts of Japan when Russia moved in. ¹

Japanese, Korean, Nivkh, and Ainu languages are all language isolates but share similarities such as preferred SOV word order, absence of gender, and not distinguishing between plural and singular form. Native speakers of Ainu are down to 15 people in the world as of 1996. ²

Apparently they have mongolian Gm blood type. ³ Dental and skeletal evidence suggests Ainus to be related to the people from the Jomon era rather than the later Yayoi people that have theoretically pushed the Ainus, or Ezos, as they were called at that time (meaning the unwanted), northward. 4 While Ainus appear to have Caucasian traits such as wavy hair, hairy bodies, thick beards, the lack of epicanthic folds, paler skin and occasional blue or grey irises, the classification of Ainu as Caucasian is not scientific. 5 Today, racial classifications based on physical features such as skin color, hair type, body proportions, and skull measurements is outdated and problematic, while the current scientific community uses genetic characteristics such as blood groups and metabolic processes to classify people. 6

Today in Japan, a person of Ainu race is addressed as "Ainu no hito" (pl. "Ainu no hitobito") as opposed to the now deprecated address of "Ainujin," in the name of political correctness. A survey in 1999 countedd 23,767 Ainus in Japan, mostly in Hokkaido. During the Meiji era, the Ainus endured oppression from the Japanese government, which was intent on colonizing the northern territories and Okinawa islands. The discrimination that the Ainus faced included the loss of land rights and criminalization of hunting, which used to be the Ainu way of life. As a step in modernization, the Meiji government imposed Japanese education on the Ainus who did not have their own writing system. Much of this has resulted in most Ainus losing their native culture. Today, equal rights is emphasised and racism is condemned. Yet the Ainus in average still live a life less wealthy than the average Japanese. 7
Sources:
  1. http://www.karafuto.com/
  2. http://www.ethnologue.com/show_language.asp?code=AIN (see usage note)
  3. http://www.dai3gen.net/epage7a.htm
  4. http://www.bears.org/spirit/ainumyth.html
  5. http://www.dai3gen.net/epage7.htm
  6. http://www.dictionary.com/cgi-bin/dict.pl?term=race
  7. http://www.city.okayama.okayama.jp/doutai/jinken/forum/forum_ainu.htm