A few different authors have tried to identify a single person as first artist in Pakistan. Though there is little historical to answer this question, that has not been an obstacle to enterprising commentators.
Perhaps it was a Karachi-based painter named Ustad Elahi Baksh:
The art originated in the days of the Raj, when craftsmen decorated horse-drawn carriages for the aristocracy. Rana, citing historian Peter Grant, said the Kohistan Bus Company hired craftsman Ustad Elahi Bakhsh and his group to decorate their buses to attract passengers in the 1920s.
From Central Asia Online, December 12, 2011
This account, however, has limited credibility, not least of all because Peter Grant is not a historian, but a New Zealand-based artist and photographer.
Another theory also places the origin in Karachi but attributes the start to Haji Hussain:
Trucks, introduced in Karachi in the 1930s were initially simply painted with a protective coat of one colour with the name of the truck company stenciled in a single colour. After partition, in the 1950s trade and port activities increased in the city and the economic prosperity of the 1950s ushered in a demand for transportation of goods. Gradually the embellishment on trucks became elaborate, evolving into a popular art form, referred to as truck art. One of the claimants to the beginning s of truck decoration was Haji Hussain who came from a long line of kamaaangars (bow and arrow makers) turned court painters in Kutch, Gujarat. At partition he brought his skills in painting murals, decorative ceilings, and statuary to Karachi and added to the stenciled trucks images of birds, flower vases, a telephone with a woman’s hand picking up the receiver on which the company’s telephone number would be written.. His sons, grandsons, and former apprentices have carried on the tradition of [chitarkari] the art of making pictures, painting trucks, sign writing or decorating furniture and decorative light panels all over Pakistan.