[4] As a result of a spiritual crisis during the Crimean War, Radstock with his wife joined the Plymouth brothers' "free" church in Bristol.

It was a community of the so-called Open Brethren, led by prominent theologian and missionary George Müller.

[5] In 1874, he travelled to St Petersburg as part of his missionary work, repeating the trips in 1875–76, and in 1878.

[6] Radstock's missionary efforts met with much success before he was expelled from Russia in 1878.

[5] Radstock married Susan Charlotte Calcraft (1833–1892) on 16 July 1858 in Holy Trinity Church, Marylebone, London.