The SPL was launched by Ratcliffe in
Edinburgh on 28 September 1920, at a large meeting of representatives from various Protestant Evangelical denominations at the Edinburgh
Free Gardeners Institute. The group proclaimed itself to be ‘evangelical, undenominational, and non-political,’ and would oppose ‘spiritualism, Christian Science, and various other systems of anti-Scriptural teaching.’ Ratcliffe served for a short time on the Edinburgh Education Authority. While he accomplished little, his membership brought him additional attention, and by the late 1920s his following had grown, including the Unionist
Lord Scone. Frustrated by what he saw as a lack of strong Protestants in the
UK parliament, Ratcliffe contested the
1929 United Kingdom general election in
Stirling and Falkirk. Ratcliffe chose the seat as the incumbent Labour MP,
Hugh Murnin, was Catholic, and the constituency had seen a dispute in
Bonnybridge over the creation of a Catholic school. Ratcliffe attacked both Murnin for his Catholicism, and the Unionist candidate
Douglas Jamieson on the strength of his Protestantism. Despite this, Ratcliffe offered to Jamieson to withdraw if Jamieson pledged to support amending the
Education (Scotland) Act 1918. Jamieson refused, losing the constituency by 5,244 votes to Murnin, with Ratcliffe receiving 6,902 votes. Following the election, Lord Scone broke with Ratcliffe and resigned from the SPL. ==Growth and electoral success==