The correct answer to this open question is the following.
Rulers of the gunpowder empires used architecture to legitimize their power as a way to express their power, control, and sovereignty over other nations. That is why they built impressive buildings for their time. Indeed they even tried to intimidate the enemy with these structures.
Some examples:
Ottoman Empire. Experts builders of Mosques. The church of Haga Sophia in Istambul is a great example.
Safavid Empire. The impressive Naqshe Jahan Square, a symbol of the grandiosity of the Safavids.
Mughal Empire. This is a classic, the world-famous Taj Mahal in India. One of the most beautiful buildings in India and probably, in the world.
