Sultan Firuz Tughlaq (1351-88 A.D.) declared that all those who turned Musalman would be exempted from paying Jizya. He says in FutuhÁt-i-Firuz Shahi… - Firuz Shah Tughlaq

I encouraged my infidel subjects to embrace the religion of the prophet, and I proclaimed that every one who repeated the creed and became a Musalman should be exempt from the jizya or poll-tax. Information of this came to the ears of the people at large, and great numbers of Hindus presented themselves, and were admitted to the honour of Islam. Thus they came forward day by day from every quarter, and, adopting the faith, were exonerated from the jizya, and were favoured with presents and honours.

Thousands of non-Muslim women were captured during the yearly campaigns of Firoz Tughlaq.

I cut off the heads of the elders of this [Hindu] sect, and imprisoned and banished the rest, so that their abominable practices were put an end to.

In places which are sacked and looted the captives are selected as per royal regulations. Those fit for royal service (alone) are sent to the court.