Indian States in Numista can be divided into the following sub-divisions,
1. Sultanates : Delhi, Bengal, Gujarat, Jaunpur, Malwa, Bahmani etc.
2. Independent Kingdoms: Mysore, Vijaynagar, Assam, Maratha Empire, Sikh Empire etc.
3. Indian Princely States: The ruling authorities Mostly under British empire
Note: Indian States also includes coins of Licchavi kingdom, which should be part of Nepal.
1. Sultanates:
From 12th century AD when Mohammad Ghori first conquered delhi, the Muslim states began forming in India. The islamic empires began setting up in northern india first and then gradually started moving south. Indian sultanates were prominent until the Mughal empire was able to subdue most of them annexing them to its empire by mid 16th century during the rule of Aurangzeb.
Coinage:
Initially during the rule of Mohammad Ghori and rulers of Slave Dynasty the motif of the coin was directly copied from hindu rajput coins. For example please see the below coin of Momd. Ghori with style (laxmi sitting) copied from rajput coins and nagari text. But progressively the coins became more islamic in nature with persian text replacing nagari.
(Coin of Mohammad Ghori)
The Sultanate issues are mostly found in Copper, Silver and Gold. Though an exception would be some issues of Muhammad bin Tughluq which were made in brass and billon. Coins of Delhi, Gujarat and Jaunpur sultanates are relatively easy to find specially the copper issues.
2. Independent Kingdoms:
Independent kingdoms (in numista terminology) mostly constitutes of hindu kingdoms which rules on various parts of india from 14th Century till 18th century. These kingdoms existed during the ruling of Mughals and British as well. The sikh empire came into prominence after Aurangzeb's death and controlled a large area of northern india during the ruling of Ranjit Singh. Sikh empire was annexed into British empire after the Anglo-Sikh wars. The Maratha empire was formed by Shivaji in 1674 AD and was in existence until 1818 AD (Second Anglo-Maratha War). The Marathas are credited to a large extent for ending the Mughal rule in India.
Coinage:
The coinage of each of the independent kingdoms varied a lot between themselves in terms of motif, style, legend. The coins of Maratha empire were mostly in Copper and silver with legends in Nagari or mostly persian. Coins of sikh empire had both gurumukhi and persian legends on them. Gold coins from both marathas and sikh empire are rare and very expensive. Octagonal Coins of assam are peculiar of that region and thus highly sought after.
(Coin of Sikh Empire)
On the other hand coins of vijaynagar were in nagari or Kannada legend). Interestingly vijayanagara coins are found mostly in copper and gold than in silver, this can be related to the scarcity of silver during that period. These coins are some of the most beautiful coins in medieval indian era.
(Coin of vijayanagara empire)
3. Indian Princely States:
The term princely state specifically refers to a semi-sovereign principality on the Indian subcontinent during the British Raj that was not directly governed by the British, but rather by a local ruler under a form of indirect rule. These princely states controlled various portions of indian subcontinent and had varied level of actual control during British era. The era of the princely states effectively ended with Indian independence in 1947. By 1950, almost all of the principalities had acceded to either India or Pakistan – nine to Pakistan and the rest to India. The accession process was largely peaceful except in the cases of Jammu & Kashmir whose king decided to accede to India, but only after an invasion by Pakistan-based tribal militia and Hyderabad, whose ruler opted for total independence in 1947, resulting in the forced annexation of the state to India.
Coinage:
Coins of princely states were issued in most of the states before British uniform coinage started from 1862. Though some states like Gwalior, Hyderabad issued their own coins up until indian independence. For some states like Alwar, bikanir etc the standard british coin design was modified slightly to add the name of the state while keeping the design, size and weight exactly same as that of India-British coinage. Interestingly some states like Jodhpur used hammered coins well into 20th century which makes it hard to recognize as a modern coin by novice coin collectors. The princely states coins differed a lot in language used which varied between nagari, persian, urdu, english etc depending on which state issued them.
(Coin of Dewas Junior Branch, From H.A.)
https://en.numista.com/catalogue/inde_princiers-1.html