Medieval Indian History GK Part 2: Who says ‘Abide pure amidst the impurities of the world’- Guru Nanak. The Tuluva dynasty was founded by- Vira Narasimha. The Bahmani kingdom reached its peak under the guidance of- Mahmud Gawan. In Akbar’s reign, the land which was cultivated every year and never left fallow is termed- Polaj.