- Madhvacharya (13th century) was a major philosopher of the Dvaita Vedanta school (dualism). He advocated for devotion (Bhakti) to Lord Vishnu, who is a personal God with attributes (Saguna). His philosophy is based on the fundamental distinction between God (Brahman/Vishnu) and the individual soul (Jiva). Thus, he propounded Saguna Bhakti. - Ramananda (14th century) was a prominent saint who is credited with popularizing the Bhakti movement in North India. He particularly advocated the devotion to Rama, an incarnation of Vishnu (Saguna Bhakti). - Vallabhacharya (15th-16th century) founded the Pushtimarga ('Path of Grace'), a school of Saguna Bhakti focused on Lord Krishna. - Nimbarka (13th century or earlier) propounded the philosophy of Dvaitadvaita ('dualistic non-dualism' or difference and non-difference), focusing on the worship of Radha and Krishna (Saguna Bhakti).