There is some evidence of genetic separation into the Wagyu genetic strain as much as 35000 years ago. Modern Wagyu cattle are the result of crossing of the native cattle in Japan with imported breeds. Crossing began in 1868 after the Meiji restoration in that year. The government wanted to introduce Western food habits and culture. Brown Swiss, Devon, Shorthorn, Simmental, Ayrshire, and Korean cattle were imported during this period. The infusions of these British, European and Asian breeds were closed to outside genetic infusions in 1910.
The variation of conformation within the Wagyu breed is greater than the variation across British and European breeds. The three major black strains – Tajiri or Tajima, Fujiyoshi (Shimane) and Kedaka (Tottori) evolved due to regional geographic isolation in Japan. These breeding differences have produced a Japanese national herd that comprises 90% black cattle with the remainder being of the red strains (Akaushi) Kochi and Kumamoto, which have been strongly influenced by Korean and European breeds, particularly Simmental.
In Japan there are four breeds that are considered Wagyu and those are the Japanese Black (the predominant Wagyu exported through the USA to Australia), Japanese Brown (Referred to as Red Wagyu in Australia), Japanese Polled and Japanese Shorthorn. There are no Japanese Polled or Shorthorns being bred outside Japan. Wagyu strains were isolated according to prefecture (state) and other breeds imported for crossing were not the same in each prefecture.
The production of Wagyu beef in Japan is highly regulated and progeny testing is mandatory. Only the very best proven genetics are kept for breeding. Realizing the value of their unique product, the Japanese Government banned the export of Wagyu in the late 1990’s and declared them a national living treasure. Zenwa is the Gov’t held entity in Japan that oversees the WAGYU registry for Japanese Black, Brown, Polled and Shorthorn.