[5][2] Kartar Singh was born into a typical Punjabi peasant family but grew to a tall height, over six-feet, and had a masculine-appearance.

[6][2] Jhabbar had become impressed by the speeches given by Mool Singh Gurmula at Virn village, which motivated him to start working for propagating the Sikh religion.

[2] In 1906, he enrolled at the Gharjakh Vidyala seminary [Khalsa Updeshak Mahavidyalaya] in Gujranwala, a training institute for Sikh preachers, where he spent three years.

[6][7] He began working as a Sikh religious preacher in 1909 and became a sewadar (volunteer) of the ongoing Singh Sabha movement, where he defended and pushed for lower-caste Hindus and Muslims to convert to Sikhism.

[2] In 1912, he established a Khalsa middle-school in Sacha Sauda village in the Sheikhupura district, in-which he appointed Sardar Arjun Singh as the school's first president.

[8] He also played an important role in the SGPC's takeover of the Harmandir Sahib (Golden Temple), the holiest shrine of the Sikhs.