How did an English police force become known as “Scotland Yard”?

In the tenth century, in an effort to stop hostilities between their two
countries, the English gave a Scottish king land in London with the pro-
vision that he build a castle on it and live there for a few months every
year. Seven centuries later, with the two nations united under one king,
the land returned to English ownership. In 1829, the London police took
up residence on the land, which by then was known as Scotland Yard.