Sardar Bahadur Rajendra Singh Of Kathgarh was born in1847 into a Mahal Jat family, was the eldest son of Khushal Singh. He became the sole surviving member of the family, aged just seven years. The young boy received a good education at the district school.
Although Rajendra Singh resided mainly at Kathgarh, his scattered Jagirs in the tehsils of Hoshiarpur, Garhshankar and Sultanwind, in Amritsar, were drastically reduced in revenue, yielding a mere Rs 3000 per annum. He later became an Honorary Magistrate, Sub-Registrar and Civil Judge, within the limits of the Balachaur Police Station, President of the Garhshankar Local Board and Member of the Hoshiarpur District Board. The title of ‘Sardar Bahadur’ was conferred upon him in 1888, and he was afterwards appointed a member of the Committee of Aitchison College, Lahore. He held a seat in the Provincial Durbars, and was seen as a man of great influence in his district. He was regarded as a unique member of the old Sikh aristocracy, that accommodated himself to the changing times. He was connected by marriage, with the houses of Sardar Nahar Singh of Ahmad Kalan, Amritsar, and Sardar She Dev Singh of Ladhran, Ludhiana. On his death, he left two minor sons, and a third one was born after his death in 1891. The Kathgarh Estate was placed under the management of the Court of Wards, and the sons were later sent to Aitchison College, Lahore, once they had reached a suitable age.
He was succeeded by his three sons;Bakhtawar Singh, Mahendra Singh and Gajendra Singh. Interestingly, Mahendra Singh became the blood brother of the Raja of Suket in Himachal Pradesh, who personally assisted him to recover his lost ancestral estates. He was married in Khumano, Ludhiana, and all his four sons were employed in government service.