Satyendra Prasanno Sinha was born in Raipur in Bengal in 1863. He entered Presidency College, Calcutta, in 1878, married Gobinda Mohini, with whom he had four sons and three daughters, in 1880, and left for England in 1881 without taking a degree.
In England he joined Lincoln's Inn where he won a scholarship of £50 a year for four years to study Roman Law, Jurisprudence, Constitutional Law and International Law. Later he also won the Lincoln's Inn scholarship of £100 for three years. Sinha was called to the Bar in 1886 and finished his education by touring the European continent. In 1886, he returned to Calcutta where he joined the City College as a lecturer in law and he also practised as a barrister.
In 1905 Sinha was appointed as advocate-general of Bengal, a post that was confirmed in 1908, and in 1909 Lord Morley appointed him legal member of the Governor-General's Executive Council, the first Indian in this position. In 1915 he was elected President of the Indian National Congress. In 1917, Sinha returned to England to work for Secretary of State, E. S. Montagu, first as an assistant, and later as a member of the Imperial War Cabinet and Conference along with the Maharaja of Bikanir. In London he stayed with William Wedderburn for a few days. He received the freedom of the City of London in 1917, took a place on the King's Counsel in 1918 (the first Indian to do so), and in 1926 was made a bencher of Lincoln's Inn. In 1919, he was made Under-Secretary of State for India, raised to the peerage of Baron Sinha of Raipur and saw the Government of India Act of 1919 through the House of Lords. He returned to India in 1920.
It is known that his third son, Sushil Kumar, studied at Colet Prepatory School in Hammersmith (1907-9), St Paul's School, London (1909-13) and Balliol College, Oxford (1913-7) and joined the Indian Civil Service but appeared to settle in England. In 1926, Sinha joined the Judicial Committee of the Privy Council in London but his health forced him to winter in India. He died in Berhampore, Bengal, on 4 March 1928.