The 1904-1905 Welsh Revival was the largest full scale Christian Revival of Wales of the 20th century. At least 100,000 people became Christians during the 1904–1905 revival. Even so, it did not put a stop to the gradual decline of Christianity in Wales, only holding it back slightly. Despite this, by 2011 South Wales (and especially settlements in the former coalfield area) showed the highest proportions of no religion anywhere in the country, rising in places to over 50%. The reasons for this are unclear.