The origins of Śaktism as Goddess worship can probably be traced to the Indus Valley culture, and iconographical evidence dates back to the pre-Christian era. The goddess Durgā appears as a powerful deity in the sixth book of the Mahābhārata and the fifth book of the Viṣṇu Purāṇa (5th cent. CE), but it is in the Devīmāhātmya portion of Mārkaṇḍeya Purāṇa (7th cent. CE) that the Goddess (Devī) is worshipped as supreme. In texts called Tantras and Śākta Upaniṣads we find a developed Tantric form of worship of the Goddess as Śakti.
The Śākta Tantras are closely allied to monistic or Kashmir Śaivism and adhere to a non-dual theology with either Śakti or the union of Śiva and Śakti as absolute. Most Śākta Tantras declare themselves to be of the Kaula or Kula school and can be divided into two main categories: (i) the Śrī Kula, which advocates worship of the benign and beautiful goddess Śrī/Lakṣmī as Tripurāsundarī; and (ii) the Kālī Kula, which advocates worship of the fierce goddess Kālī. A smaller third category advocates worship of the Goddess Tārā. The Śākta sādhaka (practitioner) will follow one or other cult prescribed for him by the guru according to his personality.
Śaktism developed, and is still practised principally, in Bengal and Assam, though worship of the goddesses at village level is found throughout India, especially in the south. Śaktism exalts the position of women by regarding them as incarnations of the Goddess; it is a mistake, however, to regard Śaktism as a force for improving the social conditions of women or low castes. Equality is only in ritual, and the role of woman is to act as a partner (śakti or dūtī) for the male sādhaka.
"Śāktism." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (August 17, 2018). http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/saktism
"Śāktism." The Concise Oxford Dictionary of World Religions. . Retrieved August 17, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/saktism