The partition of the Punjab offered the Sikhs perhaps the grimmest prospects. Concentrated in central divisions of Lahore, Lyallpur, Montgomery, Jullunder, the Sikhs were threatened with a split down the middle should a partition line be drawn on the basis of Muslim and non-Muslim majority districts. Lahore, Rawalpindi and Multan divisions, contained sizable Sikh population and many of Sikhism's most sacred places, including Nankana Sahib, would go to Pakistan. Their fertile canal colonies in the south-western districts of Montgomery and Lyallpur would certainly be lost once a partition was effected.
Summary of book "The Aftermath of Partition" by Gyanesh Kudaisya and Tan Tai Yong