Madhav Sadashivrao Golwalkar (19 February 1906 – 5 June 1973), popularly known as Guruji, was the second Sarsanghchalak ("Chief"[1]) of the Hindutva organisation Rashtriya Swayamsevak Sangh (RSS).

Sadashivrao, a former clerk in the Posts and Telegraphs Department became a teacher in the Central Provinces and Berar and ended his career as headmaster of a high school.

[14] Golwalkar went to Madras to pursue a doctorate in marine biology, but could not complete it because of his father's retirement;[11] he later taught zoology for three years at BHU.

His students called him 'Guruji' because of his beard, long hair, and simple robe, a practice later continued in a reverential manner by his RSS followers.

[13][17] In October 1936, Golwalkar abandoned his law practice and RSS work for the Sargachi Ramakrishna Mission ashram in West Bengal to renounce the world and become a sanyasi.

[19] After Golwalkar rejoined the RSS, Hedgewar began grooming him for leadership and he was placed in charge of the All-India Officers' Training Camp from 1937 to 1939.

Golwalkar's abilities (managing complex details of the large camp, public speaking, reading, and writing) were appreciated.

[9] In retrospect, Hedgewar's grooming (including encouragement to obtain a law degree and the authorship of We, or Our Nationhood Defined), is seen as key to Golwalkar's later success.

One reason for his choice is that he was thought likely to maintain RSS independence, otherwise liable to be regarded as a youth front of the Hindu Mahasabha.

[24] As RSS' leader for more than 30 years, Golwalkar made it one of the strongest religious-political organizations in India; its membership expanded from 100,000 to over one million, and it branched out into the political, social, religious, educational, and labor fields through 50 front organisations.

[26][27][28] Golwalkar's religiosity and apparent disinterest in politics convinced some RSS members that the organization was no longer relevant to the nationalist struggle.

Several swayamsevaks defected and formed the Hindu Rashtra Dal in 1943, with an agenda of a paramilitary struggle against British rule; Nathuram Godse (Gandhi's assassin) was a leader of that group.

Golwalkar recruited local Congress leaders to preside over RSS functions, demonstrating the organisation's independence from the Hindu Mahasabha.

[29] Organisation policy during the war years was influenced by potential threats to Hinduism, with the RSS expected to be prepared to defend Hindu interests in the event of a possible Japanese invasion.

At the peak of the freedom struggle Golwalkar had famously uttered "Hindus, don't waste your energy fighting the British.

The mass arrests, violence against members, and the ban by an independent Indian government of what was understood as a patriotic organization was a shock to the RSS membership.

[55] According to Ramachandra Guha's book Makers of Modern India, Golwalkar saw Muslims, Christians, and communists as the biggest threats to the creation of a Hindu state.

[56] For instance, Golwalkar's book We, or Our Nationhood Defined, published in 1939, includes the following quote: "To keep up the purity of the nation and its culture, Germany shocked the world by her purging the country of Semitic races – the Jews.

Germany has also shown how well-nigh impossible it is for races and cultures, having differences going to the root, to be assimilated into one united whole, a good lesson for us in Hindustan to learn and profit by.”[57]However, Golwalkar "cooperated" with the British in World War II in their war against Hitler and Nazism, and the Axis Powers, and was supportive of the Jews, showing admiration and sympathy for them.

Golwalkar believed that people following Semitic faiths (particularly Muslims and Christians) must either adopt or respect Hindu culture, otherwise they do not deserve the rights the citizens.

[61][62]The Central Government's motion to rename the second campus of Rajiv Gandhi Centre for Biotechnology after Golwalkar led to controversy in Kerala.

[63][64] Shashi Tharoor, in a series of tweets, asked whether the center should "memorialize a bigoted Hitler-admirer who in a 1966 speech to VHP asserted the supremacy of religion over science".