It is somewhat probable that he (or the chieftain upon whose life the legend about Ōjin is built) flourished in early 5th century.
Ōjin is his Chinese-style posthumous name. His real name was Homutawake or Hondawake (誉田別).
According to the Kojiki and the Nihonshoki, Ōjin was the son of the Emperor Chūai and his consort Jingū. As Chūai died before Ōjin's birth, his mother Jingū became the de facto ruler. The legend, presumably concocted much later, alleged that the boy Ōjin was conceived but unborn when Chūai died. His widow, Jingū, then spent three years in conquest of a promised land, which is conjectured to be Korea, but the story is largely dismissed by scholars for lack of evidence. Then, after her return to Japanese islands, the boy was born, three years after the death of the father. Either a period of less than nine months contained three "years" (some seasons), e.g. three harvests, or the paternity is just mythical and symbolic, rather than real. Ōjin was born (in 200 according to the traditional, but untrustworthy TC date, timetable; realistically sometime in the late 300's) in Tsukushi on the return of his mother from the invasion of the promised land and named him Prince Hondawake. He became the crown prince at the age of four. He was crowned (in 270) at the age of 70 and reigned for 40 years until his death in 310, although none of the TC dates around his reign have any historical basis. He supposedly lived in two palaces both of which are in present day Osaka.
He was recorded as the father of Emperor Nintoku, who became Ōjin's successor.
Jin Jiang International Hotel Management Company to Open Liangdu Jin Jiang Hotspring International Hotel, Liupanshui City, Guizhou Province
Aug 06, 2013; By a News Reporter-Staff News Editor at China Weekly News -- Jin Jiang International Hotel Management Company officially...