The fires which consumed the San Francisco business district after the 1906 earthquake upended the lives and careers of hundreds of thousands of people.

More than 75,000 left town permanently.

Another quarter of a million were left homeless.

They spent months living in tent cities built and managed by the Army.

Small businesses set up shop quickly on their sidewalks.

But old, established businesses had a harder time resuming operations.

It was especially difficult for big banks, whose metal vaults had become superheated in the fire.

Opening them before they cooled risked the spontaneous combustion of their contents — cash, gold and silver and customer valuables — with the onrush of oxygen; and these vaults took weeks to cool down.

But the big banks’ dilemma presented an opportunity for Amadeo Giannini.

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