Achar pickles come from a long tradition of pickling in India. In the Tigris Valley, the pickling of cucumbers can be traced back to 2030 BC. Though the principle ingredient of the achar might be any one of several delicious fruits or vegetables, including lime, lemon, mango, ginger, or eggplant, the decisive ingredient in all of these is the chili pepper. Some regions of India specialize in pickling meats, seafood and the ever-popular unripe mango. Pickling agents also vary. Brine, oil, and vinegar are typical pickling agents, but some recipes make use of fermented palm toddy as well.
The Definitive Glossary of British India details one of the first written records of achar in 1563 AD in works by Garcia da Orta, a Portuguese physician who describes a conserve of cashew with salt which he refers to as Āchār. The word achar has two possible etymological roots, the Hindi ächār and the Persian ācār. Recognisable derivations of the word are found throughout the Indian Ocean, with Sinhalese accāru, Tamil accāṟu, Dhivehi asaara, Malay acar, Creole French achards, Afrikaans atjar, and Yemeni Arabic ‘ushshār. As far away as japan we find the acharazuke, another likely descendant consisting of finely chopped pickles flavoured with red pepper, vinegar and salt or soy sauce.
Some scholars claim that achars may have been brought to India by the Mughals in the 16th century. At the same time, they were distributed throughout the Indian Ocean with the arrival of Portuguese traders in India. Achar pickles were favored for their capacity to keep for a long time in ship cargo holds and add piquancy to the seamens’ usual bland diet of rice and biscuits. They were also important commercial goods.