In the late 50's and early 60's the technical environment was relatively simple, when compared to today's environment. Usually one or two main computers handled all of the data processing need. Professional staffs had reams of policies and procedures to control every aspect of data center management.
Trained data processing professionals were the only ones allowed to handle and manipulate the data.
Data Center's equipment was provided by a limited number of vendors. These equipment manufactures also usually had large support staffs to help you should you have a problem.
A few farsighted companies and vendors of IT services begun to realize how important the Data Center had become to the financial well-being of a company. They realized that their companies many not survive should these technical resources be destroyed.
To prevent this catastrophe, they started to develop plans and services that would allow companies to reestablish their Data Centers quickly. They called this process Disaster Recovery. Their major focus was on what to do after an event had disabled the Data Center.