Delhi Sultanate Architecture
Quwat ul-Islam, Delhi, 1196 AD
Beginning about 1100 AD, invaders from the Abbasid Empire conquered most of northern India. These invaders were Muslims, and they needed mosques to pray in. So they got Indian builders to build them a lot of new mosques - big ones, to show how powerful and rich the new conquerors were. They built the earliest mosque in Delhi, the Quwat ul-Islam, out of stones from Hindu temples that the invaders tore down. Like West Asian mosques, this one has a large courtyard surrounded by a covered walkway with columns.
Tuglaqabad fort, 1300s AD
The Muslims didn't conquer southern India, so people kept right on building Hindu temples there. A lot of Indian architects and builders who didn't want to work on Islamic mosques moved to southern India at this time, so that the Hindu temples in the Hoysala kingdom in southern India started to mix northern and southern styles, and also to develop some new ideas.
Halebid temple, for example, has five inside rooms instead of just one, and they're arranged in the shape of a star, so the whole temple is star-shaped instead of rectangular. There is just one porch (mandapa) for all of the rooms. The temple has carvings all over showing the lives of the Hoysala kings and stories about Hindu gods.
The Konarak Temple is another example of Hindu temples in south-eastern India from this period. King Narasimhadeva built it about 1250 AD as a temple to the sun god Surya. The whole temple is shaped like a giant chariot, and covered with carvings of demons, gods, elephants, sea monsters, men and women. A carving of a giraffe shows that people from East India were travelling to Africa at this time (as does India's influence on African architecture.)
Learn by doing: visit a mosque
The Mughal Empire in India