The festival history has started in 1813 in Hyderabad & Secunderabad regimental bazzar. Plague disease broke out in Twin Cities of Hyderabad & Secunderabad, claiming thousands of lives. Before this a military battalion of Hyderabad is deployed to Ujjain, knowing about the Plague in Hyderabad the military battalion prayed to the Mother Goddess in Mahankaal Temple – Ujjain, Madhya Pradesh, that if people were saved from the epidemic they would install the idol of Mahankali back in their city. It is believed that Mahākālī destroyed the disease and keeps pestilence at arms length. Military Battalion came back to the city & installed an Idol and every year people offered Bonalu to Mother Goddess Mahankali.
Other version also includes the mythological story and belief that revolves around the festival, says that this is the time when Goddess Mahakali comes back to her parental home, in Ashada Maasam or the period from late June to August. Like daughters are much pampered in their parental homes.
Bonalu or Mahankali bonalu is a Hindu Festival, Goddess Mahakali is worshiped. Bonalu is an annual festival of Telangana celebrated in Twin Cities Hyderabad, Secunderabad and other parts of Telangana, India.It is celebrated in the month of Ashada Masam, in July/August. Special poojas are performed for Yellamma on the first and last day of the festival.The festival is also considered a thanksgiving to the Goddess for fulfillment of vows.
Bonam means Bojanam or a Meal in Telugu, is an Offering to Mother Goddess. Women prepare rice cooked with పాలు-Milk, బెల్లం-Jaggery in a New Brass or Earthen Pot adorned with వేప-Neem Leaves, పసుపు-Turmeric, కుంకుమ-Vermilion and a ప్రమిధ-Lighted Diya on the top of the Pot. Women carry the pots on their heads and make offering of బోనం-Bonam along with పసుపు-కుంకుమ;Turmeric-Vermilion, గాజులు-Bangles and చీర-Saree to the Mother Goddess across the Temples.
Bonalu involves the worship of Kali and her various forms. Goddess is worshiped as మైసమ్మ-Mysamma, పోచమ్మ-Pochamma, ఎల్లమ్మ-Yellamma, పెద్దమ్మ-Pedamma, Dokkalamma, Ankalamma, Poleramma, Maremma, Nookalamma