In January 1959, Periyar went to Bangalore to participate in the All India Official Language Conference. Along with General Kariappa and Medappa, he stressed the need to retain English as the Union Official Language. In February he undertook a tour of North India and propagated his principles of rationalism, social justice and self-respect way of life.In June 1960, Periyar asked people to burn the map of India as a protest against the Central Government using the Union of India for upholding and safeguarding caste system. About 4000 people were arrested for taking part in this agitation.In 1962, Periyar wrote a special article in the Tamil Rationalist daily, Viduthalai", welcoming the present President of Dravidar Kazhagam, ThiruK.Veeramani who had offered to become a full-time volunteer of the movement giving up his lucrative profession of a lawyer.The Congress leader K.Kamaraj expressed his wish to resign Chief Ministership and work whole time to strengthen the Party. Periyar sent a telegram to Kamaraj stating that it would be suicidal to the people of Tamil Nadu and to him, if he quit the office as the Chief Minister of Tamil Nadu. But Kamaraj did not change his decision, and consequently M.Baktavatsalam became the Chief Minister on 3rd October 1963.
As recommended by the National Integration Commission under the Chairmanship of Sir C.P. Ramaswamy Iyer, the Parliament enacted a law in 1963, prohibiting the propagation of ideas demanding separation from the Indian Union. Periyar vehemently opposed the law. In April 1964, Dravidar Kazhagam conducted meetings throughout the State, condemning the Supreme Court's verdict against the State's Act fixing a ceiling to land holding.Periyar criticized the spontaneous and fierce agitation that raged through out Tamil Nadu between January 25 and February 15, 1965 against the imposition of Hindi resulting in several deaths, because it was rudderless and unorganized. In the name of protecting cows, an unruly mob, motivated by the Hindutva ideology attempted to burn the Delhi residence of K.Kamaraj and kill him on 7th November 1966. He escaped by sheer chance. Periyar strongly condemned this barbaric attack and called upon people to be vigilant to protect Kamaraj by all means. Dravidar Kazhagam supported congress party in 1957, 1962 and 1967 general elections, and opposed DMK, which formed the government in the State in 1967. Soon after, Arignar Anna (C.N.Annadurai) went to Tiruchirappalli along with all his ministers and paid his homage to his mentor. Periyar was happy when the DMK regime renamed Madras State as Tamil Nadu and made Self-respect marriages legal. It was a non-religious mode of performing marriages introduced by Periyar in late 1920s. Though law till 1967 did not recognize such marriages, thousands of them were conducted due to the influence of the principles of Self-respect.In October 1967, Periyar undertook a North Indian tour and asked people to work for the eradication of caste system. On 12th and 13th of October, he addressed a Conference of BCs, SCs, STs and minorities in Lucknow.
Periyar was deeply saddened when Arignar Anna, one of his chief disciples and an unquestioned leader of millions of Tamil Youth, passed away in his 60th year on 3rd February 1969.