He was born in 1901 at village Dumna in the then district of Ambala. He was educated first in Ambala, and then in Khalsa College, Amritsar. His father, Inder Singh, was an official in the employ of the Central Provinces Government but later became a contractor and made a fortune, and then acquired some mills of Tatanagar. Baldev Singh joined his father's business as Director of the firm called Inder Singh & Sons Ltd. Under his supervision the business well flourished. But in 1937 he decided to enter politics and contested a seat for the Punjab Assembly on Akali ticket, winning it with a comfortable majority. After that he was elected leader of the Panthic Akali Party in the Assembly. Following the death of Sir Sunder Singh Majithia a political settlement was reached between the Akalis and the Unionist Party (called Sikandar-Baldev Singh Pact) and Baldev Singh was taken in the Ministry as a representative of the Akalis. When Khizar Hayat Khan Tiwana headed the Government after the death of Sir Sikandar Hayat Khan, Baldev Singh was again appointed Minister to represent the Akali interests in the Government. Later on, he shifted to the Centre, yielding his place to Swaran Singh.Baldev Singh played a leading role in the Sikh negotiations with the Cripps Mission, the Cabinet Mission and Lord Mountbatten. Although in all these talks his effort was to find out a suitable solution of the difficult Sikh problem, yet his approach was always national rather than sectarian. Moreover, he had implicit faith in Jawahar Lal Nehru's word that full justice would be done to the Sikhs.He was taken in the Constituent Assembly as one of the Sikh nominees of the congress. A man with long ministeral experience, he was included in the Interim Government as Member for Defence. After Independence he was again taken in the Cabinet and was assigned the portfolio of Defence. He remained at the helm of Sikh affairs till 1957 when he was replaced by Swaran Singh. He died on June 29, 1961.