Chaitanya Mahaprabhu promoted devotion to Bhagwan Krishna by constantly chanting his name. That appealed to the ordinary devotees as it did not call for much learning.
Although a well-read man,
he wrote little as he was
of the view that unalloyed
devotion alone leads to Krishna and not bookish knowledge...

During the 15th century Chaitanya, also called Gauranga because of his fair skin, and Vishvambhara, promoted the sankirtan (chanting) movement in praise of Krishna in Bengal. He was also called Nimai as he was born in a hut under a neem (margosa) tree at Mayapur, in Navadvipa (Nadia). In sankirtan, the climax is called mahadbhava (highest feeling), the devotee loses consciousness of his surroundings while chanting Hari’s name; he laughs and weeps like a mad man. Chaitanya was sometimes considered mad because of the zeal with which he chanted Krishna’s name. This spiritual ecstasy is considered the ultimate in bhakti. Chaitanya proclaimed that to achieve Krishna, Vedic knowledge was not required; what was needed was pure love for God. He said, “One who has attained love for Godhead chants and dances spontaneously and naturally, not caring for the public. To spread the sankirtan movement, Chaitanya sent his disciples to Vrindavan while he travelled in Bengal and South India. “Hare Krishna, Hare Krishna, Hare Rama, Hare Rama...” is the principal chant of this Vaishnava Sampradaya. The Rama here stands for Balarama, Krishna’s elder brother, and not the Rama of Ayodhya, the son of Dasharath. In this sampradaya, Krishna is the supreme Godhead and Golok is his highest spiritual abode. Chaitanya prescribed chanting of Hari’s name as the best method to attain moksha in Kaliyuga. Although he criticized mayavadi philosophers (those believing in Adi Shankaracharya’s philosophy), this had not prevented Chaitanya from visiting the Kashi Vishvanath Mandir in Varanasi.
Apart from promoting Krishna worship, Chaitanya carried out the medieval version of re-converting Hindu converts to their parental faith. Two brothers, Rupa and Sanatana Goswami, became his disciples. These two learned Brahmins, when in the service of Nawab Hussein Shah of Bengal, had to put on a Muslim dress and adopt alien manners. Formerly, they were known as Dabir Khas (prime minister) and Shaka Mallik (private secretary) due to the nature of their work. The Nawab, himself a Hindu convert was previously known as Subuddhiray, relied on them for administering the kingdom. The Nawab spent most of his time in hunting as he cared less for his kingdom, thanks to the loyal services of the Brahmin brothers. But after the Brahmin brothers converted, the ruler felt helpless because they gave up their administrative duties. The Nawab tried to put obstacles in their way, but they managed to negotiate their way through and succeeded in joining Chaitanya. Bengal came firmly under the heel of Muslim invaders in Nimai’s time.
Mayapur (Navadvipa), where the saint (Chaitanya) was born in 1486 to Pandit Jagannatha Mishra and Sachi Devi, maintained its reputation as a centre of traditional learning despite the political upheavals that shook Bengal. After the destruction of Nalanda and other seats of learning in eastern India, Navadvipa provided shelter to scholars from those places.
Nimai was a good student, and he mastered grammar at Pandit Gangadas’s pathshala. Then he studied logic under Vasudeva Sarvabhauma, a formidable advaita philosopher. He soon turned out to be a great logician. His fellow student, Raghunath, was very ambitious and aspired to be a famous logician. Once Chaitanya effortlessly solved a proposition in logic set by Sarvabhauma, over which Raghunath had been wracking his brains. He soon found in Chaitanya a competitor who would outshine him. Raghunath had written Didhiti, a commentary on logic. Chaitanya himself wrote a commentary on logic. After reading that, Raghunath wondered in Chaitanya’s presence as to who would care for his work in comparison to Chaitanya’s. The latter set at rest Raghunath’s fears by throwing his commentary in the Ganga.
Chaitanya became a well-known scholar at a young age; he opened his own school of grammar and logic. He was married to Lakshmi by then. But he was so immersed in devotion to Krishna that instead of teaching, he would chant Krishna’s name and encourage the students to do the same. The vexed students protested at first but later relented and joined in the chorus themselves.
When he was eighteen, Chaitanya met Ishwarpuri, who was writing a book on the love of Radha and Krishna. On being requested, Nimai agreed to be a collaborator. Another momentous event in Chaitanya’s life was his meeting with Keshav Kashmiri, a distinguished interpreter of the scriptures, on the banks of the Ganga. The scholar recited some shlokas in praise of Ganga at Chaitanya’s request. To his surprise, Nimai picked one or two verses from the middle and asked the scholar to interpret them. Keshav was amazed at Nimai’s phenomenal memory. The admiration was, however, short lived when Nimai pointed out grammatical errors in the composition. Eventually, Keshav accepted the mistakes and acknowledged Chaitanya as his guru.
The chant of ‘Haribol’ which became the signature of Chaitanya soon attracted devotees, some of whom were prominent people of Nadia. One of them was Nityananda (also called Nitai), who later became the chief disciple of Chaitanya. After some time, Chaitanya’s wife died of a snakebite. Sachi Devi arranged a second marriage, this time with Vishnupriya. Chaitanya decided to become a sannyasi at the age of 24 in 1510. His mother agreed to the proposal, but it came as a bolt from the blue to Vishnupriya. After a great deal of persuasion, she gave her consent. An advaitin, Keshav Bharati, initiated Nimai into sannyasa. From then on, he came to be known as Krishna Chaitanya. Thereafter, it was a life of ceaseless wandering for Chaitanya. He undertook a pilgrimage to places connected with Krishna, chiefly Vrindavan, in the Mathura-Agra region in 1514. Previously Chaitanya Mahaprabhu had sent Rupa Goswami and Sanatana Goswami to discover the holy sites mentioned in the Bhagavat there. Then they were joined by others who came to be known as shadgoswamis: Rupa, Sanatana, their nephew Jiva, and others.
Chaitanya’s wanderings brought him to Puri where he again met Vasudeva Sarvabhauma, who began to instruct him in Shankara’s teachings. It was a self-appointed task he undertook. He told Chaitanya that he should know Vedanta, if he wished to succeed as a sannyasi. Out of respect for Sarvabhauma’s age, Nimai politely consented. When Chaitanya started refuting Shankara by quoting from the Puranas, the aged scholar became impressed and wrote a composition called Gaurangashataka in praise of Chaitanya; it was during this visit that King Prataparudra Deva became a disciple of Chaitanya. At first Chaitanya refused to meet him, as he was against pomp and pageantry. But all this changed after the Odisha king became an ardent devotee. Sarvabhauma finally became a Vaishnava and a disciple of Chaitanya.
The Puri visit turned out to be a memorable one. But at one stage Chaitanya could not tolerate certain things because of his strict moral code and wanted to leave the place immediately. His disciples, however, prevailed upon him to stay back.
His next trip was a pilgrimage to the south, where he learnt most of the southern languages. During the southern sojourn, Nimai met Ramananda Raya, a governor in the Vijayanagar empire, on the banks of the Godavari River in Rajamahendravaram (Rajahmundry), in Andhra Pradesh. Nimai at once recognized in him a realized soul. He embraced him and that was the beginning of a lasting association. Chaitanya asked Ramananda to expound the divine love between Radha and Krishna, which he did. In the end, Chaitanya himself manifested as Radha and Krishna, but told him not to tell it to others as they might take him to be a mad man to make such a claim. It is said Chaitanya succeeded in converting Karnataka to the Bhakti tradition.
After the southern trip, Chaitanya visited Maharashtra. A miracle occurred when he was at Pune while on the shore of a lake. A mischievous fellow pointed to the lake and said, “Look there is your Krishna.” Without a moment’s hesitation, Nimai jumped into the lake and very nearly drowned. After Chaitanya was rescued, the spectators started to beat the prankster. Chaitanya saved him from their wrath by saying he had done nothing wrong as Krishna is to be found everywhere. This was possible for him as he would always be in a heightened state of spiritual fervour.
Chaitanya finally returned to Puri in 1516 and stayed there for 18 years, where he spent his time in worshipping Bhagwan Jagannath. He would become ecstatic while worshipping Jagannath. Finally, he entered the sea at Puri, never to return. At such times, he took the sea to be the Yamuna at Vrindavan.
Shri Krishna Chaitanya was an eminent proponent of the Gaudiya Vaishnava School of Bhakti Yoga, that is, loving devotion (madhura bhava) to Krishna based on the philosophy of the Shrimad Bhagavata and Bhagavad Gita. He established Gaudiya Vaishnavism in East India. Though a great scholar he wrote only two beautiful works. The first has only eight verses and is called Chaitanyashikshashtaka, and the second is called Jagannathastotra.
In the 20th century the teachings of Chaitanya Mahaprabhu were spread to the West by A.C. Bhaktivedanta Swami Prabhupada (1896-1977), who founded the International Society for Krishna Consciousness (ISKCON).