Born on the Isle of Arran. He learnt journalism in Edinburgh but soon settled in London, and worked in the Secularist Movement, editing the National Reformer after the death of Charles Bradlaugh.
He was MP for Tyneside from 1906 to 1918, and was Parliamentary Secretary to the Board of Trade, 1911-15, and Privy Councillor.
With Bradlaugh's daughter, Hypatia Bradlaugh-Bonner, he founded the Rationalist Peace Society 1910-1921.
Later in life he was involved with Leicester Secular Society, being for instance principal trustee of the Leicester Rationalist Trust (owners of the Leicester Secular Hall).
His prolific writings cover a wide field: politics, economics, history, and comparative religion. Of particular Rationalist interest are his works on history of Freethought and on the mythical nature of Jesus.
Partial List of Works:
Modern Humanists (1891, 1968)
The Fallacy of Saving (1892)
Buckle and His Critics (1895)
The Saxon and the Celt (1897)
Patriotism and Empire (1899, 1990)
A History of Freethought in the Nineteenth Century, (1899, 2 vols 1929, 1969)
Christianity and Mythology (1900, 1910)
A Short History of Christianity (1902, 1931)
Pagan Christs (1903, 1911)
Essays in Sociology (1904) — 2 volumes.
Pioneer Humanists (1907)
Montaigne and Shakespeare (1909)
The Evolution of States (1912)
The Baconian Heresy (1913)
Elizabethan Literature (1914)
A History of Freethought, Ancient and Modern, to the Period of the French Revolution — (1915, 2 vols 1936, 1969)
The Historical Jesus (1916)
The Jesus Problem (1917)
The Economics of Progress (1918)
A Short History of Morals (1920)
The Meaning of Liberalism (1925)
The Dynamics of Religion (1926)
Modern Humanists Reconsidered (1927, USA 1982)
Jesus and Judas (1927)
The Decadence (1929) — under the pen-name "L. Macaulay".
Electoral Justice (1931)
Fiscal Fraud and Folly (1931)
Courses of Study (1932)