It was built by the Silver Shirts, a sinister group of 1930s fascists who took their name from Hitler’s Brown Shirts grass roots organisation.

Fascism had been on the rise in the wake of the Great Depression and the Silver Shirts were one of the most fanatical organisations.

The 55-acre ranch, was sold to mining fortune heiress Jessie Murphy in 1933 by screen cowboy Will Rogers.

In the next few years, Murphy struck up a relationship with a German man known only as Herr Schmidt. Unbeknown to her Schmidt was Hitler’s agent in America.

He persuaded her to invest $4million ($66 million today) to transform the property into a nazi stronghold fit for Hitler.