Baldev Singh was industrialist politician and the first Defence Minister of India at Independence was born on 11 July 1902, to a Sikh family of Chokar Jatts at the village of Dummna, in Ropar district of the Punjab. His father, Inder Singh, who started life as a government official in the Central Provinces (now Madhya Pradesh), later became a contractor and ultimately rose to be a steel magnate at Jamshedpur, in Bihar. Baldev Singh, after completing his education at Ambala and then at Khalsa College, Amritsar, joined his father's firm as a director. Returning to the Punjab during the mid-1930's, he made his debut in politics when he became a candidate in the first elections to the provincial assembly under the Government of India Act, 1935, held in early 1937. The family's philanthropic work in the district, especially in the field of education, earned him popular support and he won as a candidate of the Panthic (Akali) Party, a combination of Akali and Nationalist Sikhs. He along with Master Tara Singh, Sardar Jogendra Singh and Sardar Ujjal Singh was chosen to represent the Sikh community ,before the Cripps Mission which came out to India in the spring of 1942 on behalf of the British War, Cabinet with proposals for the country's political future. In June 1942, there was an understanding between Sir Sikandar Hayat Khan, Premier of the Punjab, and the Akalis, who were invited to join the coalition government headed by him. As a result of what came to be known as the Sikandar-Baldev Pact, Baldev Singh was sworn in as Development Minister on 26 June 1942. He retained his position in the Punjab cabinet until, after the death of Sir Sikandar in December 1942, a new ministry was formed under Malik Khizar Hayat Khan Tiwana. When a British Cabinet Mission visited India in 1946 to negotiate with Indian leaders about the future constitution of the country, Baldev Singh was chosen a member of the delegation to present to it the Sikh viewpoint. He also met the Mission separately to seek special protection for the Sikhs. He favors a united India with safeguards for the minorities, but, if partition of the country as insisted on by the Muslim League became inevitable, he wanted redemarcation of the boundaries of the Punjab, slicing off the Muslim-dominated divisions of Rawalpindi and Multan to secure the Sikhs the balance of power in the remaining Punjab.
On 16 May 1946, the Cabinet Mission put forward a plan which, retaining the semblance of a central structure, conceded substantially the Muslim claim for autonomy, without any special safeguards for Sikhs. The Sikhs rejected the scheme at an assembly held at Amritsar on 9 and 10 June 1946 and set up a representative body called the Panthic Pratinidhi Board to resist its implementation. Baldev Singh was one of the members of the Board. On Jawaharlal Nehru's appeal, the Panthic Board, at their meeting on 14 August 1946, while reiterating that the Cabinet Mission scheme was unjust to Sikhs, retracted their boycott of it. Baldev Singh joined the Cabinet headed by Jawaharlal Nehru as the Sikhs' nominee on 2 September 1946. He took over the defense portfolio which had, throughout the British rule, been held by the British Commanderin-Chief, who had been, in order of precedence, next only to the Viceroy and Governor-General of India. The Indian Army (as also the Navy and the Air Force) had been organized and trained as a colonial force controlled, except at the bottom rungs by British officers. That position had now to change. The Commander-in-Chief had to be under an Indian civilian minister of defense. Baldev Singh brought about the change with tact and firmness. In a radio broadcast on 9 October 1946, he enunciated the policy of the Interim National Government in these words: "We aim at building up, in a truly national way, a National Army, which will be the pride of this great land of ours. It is indeed our right to have our armed forces completely Indianised. Nobody disputes that right. Indianisation of the armed forces will now be speeded up at an accelerated pace, compatible with efficiency, and our only concern will be to maintain and better the excellence of the standard you yourselves have built up." Referring to British officers he said, "We have at present many British officers who have served the Army loyally and faithfully. It is nobody's desire that in achieving our objective we be unjust to them. They and others before them have contributed greatly in fashioning the steel that is the envy of others. I have every hope that their help and co-operation in the great task of Indianisation will be available now, as in the past. We shall value their talent and their co-operation as ever before."
Independence accompanied by partition of the country into India and Pakistan brought in its wake the second biggest task for the Defense Minister, viz. the division of personnel, equipment and military installations between the two countries, and provision of escorting convoys of refugees from and to Pakistan. New challenges came with the Pakistan-aided invasion of Kashmir and police actions in Junagarh and Hyderabad. Baldev Singh was not only a member of the Congress government, but was also a leading representative of his community which brought in its train further responsibilities. He failed to get the realization of past promises and assurances given by the Congress regarding constitutional guarantees for the protection of the rights of the Sikhs as a minority community. In the first general election held under the Constitution in 1952, he was elected to Indian Parliament (Lok Sabha) on Congress nomination (without opposition from the Akalis), but was not included in the Cabinet by Prime Minister, Jawaharlal Nehru. He was reselected to Parliament in 1957. His health began to deteriorate and after a prolonged illness he died in Delhi on 29 June 1961. His body was flown to his native village where he was cremated with full military honors.