William Booth was born in Nottingham, England, the second son of five children born to Samuel Booth and his second wife, Mary Moss. Booth's father was relatively wealthy by the standards of the time, but during William's childhood, the family descended into poverty. In 1842, Samuel Booth, who could no longer afford his son's school fees, apprenticed the 13-year-old William Booth to a pawnbroker. Samuel Booth died in 1842.
Two years into his apprenticeship Booth was converted to Methodism. He then read extensively and trained himself in writing and in speech, becoming a Methodist laypreacher. Booth was encouraged to be an evangelist primarily through his best friend, Will Sansom. Sansom and Booth both began in the 1840s to preach to the poor and the sinners of Nottingham, and Booth would probably have remained as Sansom's partner in his new Mission ministry, as Sansom titled it, had Sansom not died of tuberculosis, in 1849.
When his apprenticeship ended in 1848, Booth was unemployed and spent a year looking in vain for work. In 1849, Booth reluctantly left his family and moved to London, where he again found work with a pawnbroker. Booth tried to continue lay preaching in London, but the small amount of preaching work that came his way frustrated him, and so he resigned as a lay preacher and took to open-air evangelising in the streets and on Kennington Common.
In 1851, Booth joined the Reformers (Methodist Reform Church), and on 10 April 1852, his 23rd birthday, he left pawnbroking and became a full-time preacher at their headquarters at Binfield Chapel in Clapham. William styled his preaching after the revivalist American James Caughey, who had made frequent visits to England and preached at the church in Nottingham where Booth was a member, Broad Street Chapel. Just over a month after he started full-time preaching, on 15 May 1852, William Booth became formally engaged to Catherine Mumford.
Interested in the Congregationalist approach, Booth consulted David Thomas at Stockwell about the ministry. Through Thomas, he met John Campbell and then James William Massie. The recommendation was training under Rev. John Frost; but Booth disliked Frost's school, and left shortly. In November 1853, he was invited to become the Reformers' minister at Spalding, in Lincolnshire. He married Catherine Mumford on 16 July 1855 at Stockwell Green Congregational Church in London.
Though Booth became a prominent Methodist evangelist, he was unhappy that the annual conference of the denomination kept assigning him to a pastorate, the duties of which he had to neglect to respond to the frequent requests that he do evangelistic campaigns. At the Liverpool conference in 1861, after having spent three years at Gateshead, his request to be freed for evangelism full-time was refused yet again, and Booth resigned from the ministry of the Methodist New Connexion.
Soon he was barred from campaigning in Methodist congregations, so he became an independent evangelist. His doctrine remained much the same, though; he preached that eternal punishment was the fate of those who do not believe the Gospel of Jesus Christ and the necessity of repentance from sin, and the promise of holiness. He taught that this belief would manifest itself in a life of love for God and mankind.
A tent was set up on an old Quaker burial ground in Whitechapel. To the poor and destitute of London's East End, Booth brought the good news of Jesus Christ and his love for all. Later in 1865 he and his wife Catherine opened The Christian Revival Society in the East End of London, where they held meetings every evening and on Sundays, preaching repentance and salvation through accepting Jesus Christ as Lord and Savior to the poorest and most needy, including alcoholics, criminals and prostitutes. The Christian Revival Society was later renamed The Christian Mission. Slowly The Christian Mission began to grow but the work was difficult and Booth would stumble home night after night haggard with fatigue, often his clothes were torn and bloody bandages swathed his head where a stone had struck, wrote his wife. Evening meetings were held in an old warehouse where people threw stones and fireworks through the window. Outposts were eventually established and in time attracted converts. At that time, the Christian Mission, later to become known as the Salvation Army, was just one of about 500 groups trying to help the poor and needy in London.