I've been wanting to try Kobe beef. Have you tried it?
Yes, I have! It's delicious! The beef comes from cattle brought to Japan from China!
Wow, and what makes it so special?
The cows were basically isolated on the island of Japan until 1854 so there was no possibility of foreign genes getting into the cattle population. 
That's insane. It must have great texture.
and selected as "Improved Japanese Cattle". Four separate strains were characterised, based mainly on which type of foreign cattle had most influenced the hybrids, and were recognised as breeds in 1944. These were the four wagyū breeds, the Japanese Black, the Japanese Brown, the Japanese Polled and the Japanese Shorthorn. The Tajima is a strain of the Japanese Black, the most populous breed (around 90% of the four breeds).
Beef consumption remained low until after World War II. Kobe beef grew in popularity
and religious reasons – meat was not eaten. Cattle were highly prized and valuable, too expensive for a poor farmer to buy.
Japan was effectively isolated from the rest of the world from 1635 until 1854; there was no possibility of intromission of foreign genes to the cattle population during this time. Between 1868, the year of the Meiji Restoration, and 1887, some 2600 foreign cattle were imported. At first there was little interest in cross-breeding these with native stock, but from about 1900 it became widespread