Hazur Maharaj Sawan Singh Grewal was born into a Sikh family on 27 July 1858 in village Jatala, District Ludhiana. His father was Subedar Major Kabul Singh and his mother was Mata Jiwani. He was married to Mata Kishan Kaur and together they had three children. He passed Engineering from Thomason College, Roorkee and joined the Military Engineering Service.

He studied scriptures of various religions but retained a strong connection with the Gurbani of the Sikh religion.

He had contact with a mystic of Peshawar named Baba Kaahan who he hoped to get initiation from but was refused:

"I associated with him for several months and during that time he showed supernatural powers on several occasions. When I asked him if he would shower grace upon me by initiating me, he answered: 'No, he is somebody else; I do not have your share.' I then asked him to tell me who that person was so that I could contact him. He replied: 'When the time comes, he will himself find you.'"

Later when Maharaj Sawan Singh was stationed at Murree, he met Baba Jaimal Singh, who said to his companion that he had come to initiate Sawan. After much arguing and discussion and several conferences with Baba Jaimal Singh, Hazur Maharaj Saawan Singh became thoroughly convinced and received Initiation from Baba Jaimal Singh on the 15th day of October, 1894.

Hazur Maharaj Saawan Singh retired in 1911 and developed Dera Baba Jaimal Singh (Beas) --the "camp of Baba Jaimal Singh" where Baba Jaimal had settled in 1891—and built houses, bungalows and a Satsang Hall. Hazur Maharaj Saawan Singh sheltered victims of the communal holocaust of the Partition of India. His following included Hindus, Muslims, Sikhs, Christians, and for the first time, thousands from abroad, the US, UK, Switzerland, Germany, including Julian Johnson and Pierre Schmidt.