61-year-old Singh from Uttar Pradesh, who takes over from Nitin Gadkari, returns to the political terrain in which the low-profile, soft-spoken and articulate leader found himself about six years ago when he was chosen by the saffron party to head it. General elections is due in May 2014.
Singh's dramatic elevation to the top party post caps a period of big political churnings within BJP divided on re-electing Gadkari as president for a second time.
It was Singh who had handed over the baton to Gadkari in December 2009. But in a sudden and dramatic last-minute twist, Gadkari, facing allegations of dubious funding of his company, was last night forced out of the race for BJP President's post for a second term and Rajnath emerged the consensus choice.
The party probably had little choice except to fall back on Singh's non-controversial image and a high degree of acceptability among rival groups in the organization.
Singh has again been brought back by the party as chief just three days after the Congress elevated AICC general secretary Rahul Gandhi as Vice President.
How Singh will reshape the BJP to counter Congress' charm offensive remains to be seen though he has often lauded BJP's democratic strength which has enabled a "commoner" like him to lead the party
From a college lecturer in Physics, Rajnath Singh's rise in politics has been gradual and steady during which he had been BJP chief from 2006 to 2009 and earned the reputation of being an able administrator as Union Minister twice and Chief Minister of Uttar Pradesh.
Currently a Lok Sabha member from Ghaziabad, Singh has emerged from the ranks as a political heavyweight in the party largely due to his proximity to BJP's spiritual mentor RSS.
After taking over BJP's reins from veteran leader L K Advani in December 2005, Rajnath Singh sought to rebuild the party by focusing on basic Hindutva ideologies and said there would be "no compromise" on building the Ram Temple in Ayodhya.
However, he not only failed to steer the party to power in the 2009 general elections but BJP's poll tally dropped by 22 seats compared to 2004 Lok Sabha polls.
Born on July 10, 1951 at Bhabhaura village in Uttar Pradesh's Chandauli district, Singh obtained MSc degree in physics from Gorakhpur University and was appointed lecturer in the K B Post graduate degree college in Mirzapur in 1971.
Singh's association with Rashtriya Swayamsevak Sangh began in 1964 when he was only 13 year old. Even as lecturer he remained attached to RSS.
Rising step by step, he began his political innings with BJP's student wing Akhil Bharatiya Vidyarthi Parishad (ABVP) in 1969 as its organising secretary in Gorakhpur and rose to become the secretary of the then Bharatiya Jan Sangh's Mirzapur unit in 1974.
During the Emergency, Singh joined Jaiprakash Narayan's movement and was arrested in July 1975 before being released in 1977.
Singh made his debut in electoral politics when he became an MLA in Uttar Pradesh in 1977. In 1983, he became state Secretary of BJP and a year later he found himself leading the Uttar Pradesh unit of BJP's Youth Wing (BJYM).
His political rise continued with his elevation as National General Secretary of BJYM in 1986 and subsequently its National President in 1988.
In the same year, Singh was elected Member, Legislative Council in UP, a position he held till 1994, serving in between as Education Minister in the Kalyan Singh government until it was dismissed in December 1992 following the Babri Masjid demolition.
As Education Minister in UP, Singh had courted controversy by enacting the Anti-Copying Act which had opposition parties up in arms against him.
Born on 10th July 1951 in a farmer's family at village Babhora, Tehasil Chakia, District Varansi (now district Chanduli) UP, to Shri Rambadan Singh and Srimati Gujarati Devi.
He was a brilliant student and an active RSS worker since his student life. He became the RSS karyavah (General Secretary) of Mirzapur city in 1972. Also remained organisational secretary of ABVP Gorakhpur division from 1969 to 1971.
He entered politics in 1974 and soon became Secretary of Bharatiya Jana Sangh, Mirzaur. In 1975, he became District President of Jana Sangh and District Coordinator of JP Movement.
He was imprisoned during Emergency. During this period (18 months) his mother expired but he was denied parole to attend her funeral.
In 1977, he was elected as an MLA in UP Assembly.
In 1983, he became a State Secretary of UP BJP and 1984 he became a State President of BJP's Youth Wing (BJYM). In 1986, he became National General Secretary of BJYM and subsequently National President of BJYM in 1988.
He was elected MLC for UP Legislative Council in 1988 and became Education Minister in 1991. During his tenure as Education Minister in UP he established some landmarks by introducing the Anti Copying Act and Vedic Mathematics in the syllabus and correction of various portions of' history textbooks.
He became MP Rajya Sabha in 1994 and also the Chief Whip of the BJP in Rajya Sabha.
On 25th March 1997, he became State President of UP BJP. During this period apart from expanding and strengthening the organisation, he played a key role in saving the BJP led Government twice during the political crisis.
On 22nd November 1999, he became Union Surface Transport Minister. During this period he got the opportunity to initiate the NHDP (National Highway Development Programme), a dream project of Shri Atal Bihari Vajpayee.
On 28th October 2000, he became Chief Minister of UP and was twice elected as MLA from Haidargarh constituency in Barabanki. In 2002, he became National General Secretary of BJP.
On 24th May 2003, he became Union Minister of Agriculture and subsequently for Food Processing. During this period he initiated a few epoch making projects like Kisan Call Centre and Farm Income Insurance Scheme.