How did the expression 'I'm in a pickle...' come about?

Senior Moments

From the American Heritage Dictionary: Trade with the Low Countries across the North Sea was important to England in the later Middle Ages, and it is perhaps because of this trade that we have the word pickle. Middle English pikel, the ancestor of our word, is first recorded around 1400 with the meaning 'a spicy sauce or gravy served with meat or fowl.' This is a different sense from the one the word brings to mind now, but it is somewhat related in sense to its possible Middle Dutch source pekel, a solution, such as spiced brine, for preserving and flavoring food. After coming into English the word pickle expanded its sense range in several ways. It was applied, as it had been in Middle Dutch, to a pickling solution. Later pickle was used to refer to something so treated, such as a cucumber. The word also took on a figurative sense, 'a troublesome situation,' perhaps under the influence of a similar Dutch usage in the phrase in de pekel zitten, 'sit in the pickle,' and iemand in de pekel laten zitten, 'let someone sit in the pickle.' Jan 03 02, 4:43 PM

Tiresias

Adding to what Senior Moments says, it was used by Shakespeare: 'How cam'st thou in this pickle'. Tempest Act 5 Scene 1 Jan 03 02, 7:45 PM