Giani Ditt Singh was a scholar, poet and journalist. He was an eminent Singh Sabha member and editor. He was born on 21 April 1853 at Kalaur, a village in Patiala district of Punjab. His ancestral village was Jhalhan, near Chamkaur Sahib, but his father, Divan Singh, had migrated to his wife's village, Kalaur. Divan Singh, a weaver by trade, was a religious minded person who had earned the title of Sant for his piety. Himself an admirer of the Gulabdasi sect, he sent Ditt Singh at the age of nine, to be educated under Sant Gurbakhsh Singh at Dera Gulabdasian in the village of Tior, near Kharar in Ropar district. Ditt Singh studied Gurmukhi, prosody, Vedanta and Niti-Sastra at the Dera, and learnt Urdu from Daya Nand, a resident of Tior. At the age of 16-17, he shifted to the main Gulabdasi centre at Chhathianvala, near Kasur in Lahore district. Formally initiated into the sect of Sant Desa Singh, he became a Gulabdasi preacher. Not long afterwards, he came under the influence of Bhai Jawahir Singh, a former follower of the Gulabdasi sect, who had joined the Arya Samaj. Ditt Singh also became an Arya Samajist. He was introduced to "Swami" Daya Nand Sarswati, the founder of the Arya Samaj, during the latter's visit to Lahore in 1877. Soon, however, he and his friend, Jawahir Singh, were drawn into the Sikh fold through Bhai Gurmukh Singh, the motive force behind the Lahore Khalsa Diwan. In 1886, Bhai Gurmukh Singh, following the establishment of the Lahore Khalsa Diwan parallel to the one at Amritsar, floated the first Punjabi weekly newspaper, the Khalsa Akhbar. Though its first editor was Giani Jhanda Singh Faridkoti, the principal contributor was Giani Ditt Singh, who soon took over editorship from him.

He had passed the Gyani examination the same year and had been appointed a teacher at the Oriental College. In his hands the Khalsa Akhbar became an efficient and powerful vehicle for the spread of Singh Sabha ideology. The Khalsa Diwan Amritsar led by Baba Khem Singh Bedi and the ruler of Faridkot, Raja Bikram Singh, had Bhai Gurmukh Singh excommunicated, under the seal of Darbar Sahib, in March 1887. On 16 April 1887, Giani Ditt Singh issued a special supplement of the Khalsa Akhbar in which appeared a part of his Supan Natak (q.v.), or Dream Play, a thinly-veiled satire, ridiculing the Amritsar leaders and their supporters. One of the victims of the burlesque, Bava Udey Singh, filed a defamation suit against Giani Ditt Singh in a Lahore court. The latter was sentenced to pay a fine of Rs 5 but was on appeal acquitted by the sessions court on 30 April 1888. The case had dragged on for over a year, imposing severe financial hardship on the Khalsa Akhbar. It had already suffered a setback by the death in May 1887 of its chief patron, Kanwar Bikrama Singh of Kapurthala. In 1889, it had to be closed down, along with the Khalsa Press. Bhai Gurmukh Singh, however, secured, through Bhai Kahn Singh, help from the Maharaja of Nabha and the Khalsa Akhbar recommenced publication on 1 May 1893. Editorship was again entrusted to Ditt Singh. Ditt Singh also helped Bhagat Lachhman Singh to launch from Lahore on 5 January 1899 the Khalsa, a weekly in English. Giani Ditt Singh and his friend, Jawahir Singh, had not publicly severed their connection with the Arya Samaj even after their initiation into the Sikh faith. The final breach came on 25 November 1888 when, in a public meeting held on the eleventh anniversary of the Lahore Arya Samaj, Pandit Guru Dutt of Government College, Lahore, and Lala Murh Dhar spoke disparagingly about the Sikh Gurus. This hurt the feelings of Giani Ditt Singh and Bhai Jawahir Singh and they left the Arya Samaj for good. They joined hands with Bhai Gurmukh Singh and threw themselves whole-heartedly into the Singh Sabha work.

Giani Ditt Singh wielded a powerful pen and was equally at home in prose as well as in verse. He wrote more than forty books and pamphlets on Sikh theology and history and on current polemics. Well-known among his works are: Guru Nanak Parbodh, Guru Arjan Charittar, Dambh Bidaran, Durga Parbodh, Panth Parbodh, Raj Parbodh, Mera até Sadhu Dayanand da Sambad, Naqh SiAh Parbodh and Panth Sudhar Binai Pattar. He also published accounts of the martyrdom of Bhai Tara Singh Wan, Bhai Subeg Singh, Bhai Mehtab Singh Mirankotia, Bhai Taru Singh and Bhai Bota Singh. Ditt Singh's marriage took place in Lahore in 1880 according to Sikh rites. His wife, Bishan Kaur, shared his religious zeal and the couple had a happy married life. They had two children, a son, Baldev Singh, born in 1886, and a daughter, Vidyavant Kaur, born in 1890. Ditt Singh was very fond of his daughter who was a very precocious child. Her death on 17 June 1901 was a great blow to Ditt Singh, who had already been under a strain owing to persistently heavy work since the death in 1898 of Bhai Gurmukh Singh. He still continued to work with patience and fortitude, but his health deteriorated rapidly and he fell seriously ill. A Muslim doctor, Rahim Khan, treated him but even his best efforts were of no avail. Giani Ditt Singh died at Lahore on 6 September 1901. The loss was mourned widely by the Sikhs. A 15-member memorial committee was formed with Bhai Sahib Arjan Singh Bagarian as chairman. Notable memorials honouring his name were Giani Ditt Singh Khalsa Boarding House in Lahore and Bhai Ditt Singh Library opened at Sikh Kanya Mahavidyala Firozpur by Bhai Takht Singh, one of his former students and a close friend.