Its Muslim but not Pakistani.
Pakistani history is basically everything that took place on Pakistani land since thats where most Pakistanis have always lived. i.e Indus Valley, Ghandaran Kingdom, Porus Kingdom etc.
The Taj Mahal is Indian because it is in India, its Muslim because it was built by a Muslim ruler, who was Central Asian for the record.
Pakistanis however are proud of such monuments because they show the face of Muslim rule in India.
Religion doesnt change who your ancestors were. Having the same Religion doesnt give you right over land or history which didnt belong to your ancestors either.
With all due respect to you :--
Pakistan's history comprises of only the events leading to creation of pakistan and thereafter.... i.e Since 1940-till date , give or take few years before 1940...
Indus valley civilization , Gandhar rajya(kingdom) , Puru Kingdom (porus was the king) etc. are part of India's history. Just because the place where the events took place are in present day pakistan does not makes them part of pakistan, pakistani culture or indeed pakistan's history.
Below are few facts about these places at that time:--
1. Indus valley civilization was an ancient hindu civilization and you find references of it in ancient hindu texts i.e vedas, purans etc.
2. Gandhar rajya plays an important part in Mahabhart, you can find out about it if you read it or ask me if you would really like to know.
3. Puru rajya was also an hindu kingdom rules by hindu king.
Pakistan cannot simply claim that part of history which suits her and discard part of history that it does not likes. All above things are part of India and her history... Pakistan unfortunately cannot lay claim to it...
Some other facts ---
a) You will find references of sindhu desh in Mahabharat. The king fought on Kauravs side and was slain in battle.
b) Lahore is named after Lord Ram's Son. Lahore Fort has a vacant temple dedicated to the son of Lord Ram
c) Jammu & kashmir is named after a hindu rishi kashyap. It is believed that he was the one who drained lake from the valley and that is why the place is named after him.
The reason for above facts is not to start trolling here but they should be seen in the context of the topic being discussed.