As far as pickles are concerned, I don't know what the earliest surviving written recipe for them is, but pickling as a method of food preservation has been going on for thousands of years. The earliest references to it seem to come from Mesopotamia, about 2400 B.C. We know that Cleopatra included eating pickles in her beauty regimen, while her significant other (one of them) Julius Caesar fed them to his troops because he believed that eating pickles made them stronger. Perhaps he should have eaten a few more himself.
The English word "pickle" is derived from the Dutch term pekel, which refers to the brine.