Before the invention of cold storages and refrigerators food was consumed within a few miles of where it was produced and consumed within a very short time of it being harvested. Grains, Rice, Lentils could be stored but fresh fruits and vegetables had to be consumed at the earliest.
At that point of time people ate fruits and vegetables that were Local, Seasonal and Fresh. The main challenge that existed was the weather. In cold regions nothing would grow in the winter and in hot regions nothing would grow in the scorching summers, then how could a mother/grandmother feed her family fruits and vegetables throughout the year.
Over the years, to solve this problem, humans worked on the art of food preservation, to be able to feed the family nutritious food even during the worse weather conditions and thus the art of pickling was born.
In colder regions in the summer months they would salt the meat, sun dry the fish, sugar the fruits (Jam & Marmalades) and put vegetables in vinegar (Western style of Pickling) for consumption during the harsh winter months.
We in India were blessed with more options, in the winter and in the summer fruits and vegetables were pickled using 5 natural preservatives Spices, Salt, Oil, Vinegar and sweeteners (Jaggery, Shakaretc) preserving all their natural goodness
During the scorching summers it was these mouth watering pickles that were used in place of fresh fruits and vegetables to provide nutritious options to feed the family and to a large extent the Art of Pickling was created out of necessity for Survival.