The Rouniyar (also called Rownier, Roniaur, Rauniyar) are a sub caste group within the supreme vaish community which is under category of other backward caste/general in nepal country ( as frames by the Central Government of India per Indian constitutions act 1950)in few other states they come under scheduled Caste also , however Roniaur section demands for any reservation from government and always rejected by the Administration but they always focus on business and merit but government due to jealous and personal rivalries includes in reservation category to show them high moreover some mischievous elements try to themselves highly respected bania caste into lower category that is unfair and anti human also moreover in post independence period this caste was in scheduled class group in Bihar and UP but after independence it is brought down under backward class list hencefore bania are claim both as per State Government List wise , and they get their name from the Hindi word 'rauna'.However ancestors of rauniyar caste were Rajput and Brahmin later they adopted business as claimed by them.They are found throughout Bihar, Eastern UP, Jharkhand, West Bengal, Chhatishgarh, Eastern Nepal,North East Region Assam but their main concentration is the Sasaram/ Ballia. In addition, there are also small communities found in Gorakhpur, Lucknow, Mirzapur, Ballia, Lucknow, Kanpur Varanasi in Uttar Pradesh and the Saran District, Patna, Danapur, Arrah, Ranchi, Bokaro & Hajipur in Bihar. They speak Hindi/ Bhojpuri/ Awadhi / Maithili among themselves, and Hindi with outsiders. Like other Banias, they are non vegetarians as well vegetarians.
In Bihar, the Rauniyar are also known as Rouniyar. They claim to have come from Awadh some three hundred years. The Roniaur are found mainly in the districts of Muzaffarpur, East Champaran, West Champaran, Munger, Bhagalpur, Nawada Gaya and Dumka, Deoghar, Godda, Ranchi and every parts in jharkahand and other states likes North East States Likes Assam, Bengal ]. Their common surnames are Sah, Sahu,Sa,Shaw,Sha,Shah , Sahani , Prasad, Gupta, Bhagat, Gupt, Lochan, Saran sometimes Singh too. They are strictly endogamous, and practice clan exogamy. They (Rauniar Bania) speak Maithili in north east Bihar and Bhojpuri in western Bihar . 
According to the list of Assam and other other north east region scheduled Caste list 1950 & 1956 of Indian Constitutions as frames by the Central Government of India they as listed as Bania & they are claim as scheduled caste in few in the State of Assam, Meghalaya , Monipur, Arunachal Pradesh even in Bihar also in the year of 1985 they treated as scheduled caste Annexure I & II, and many other states they claim as Other Backward Class as their own literacy economic/financial position.
The Rouniyar/Roniaur Bania /(बनिया) are a business community, and their traditional occupation has been the selling of food grains,clothes and lending money as banker. They are often the shopkeepers in the villages of north Awadh. A few Roniaur were very royal jagirdars, but they rarely ever cultivated their own land, depending on sharecroppers. Their customs are similar to other Awadh Bania, such as the Omar.
In Bihar, the Rouniyar /Roniaur Bania (बनिया) were both traders and landowners. Many were substantial jagirdars, but with the land reforms carried out after independence in 1947, and seen a break up of the larger estates in Bihar. Like other Bania communities, they are partially poor and undergoing urbanization. They are comes under obc category which is declare by the Government of India under the constitutions ( other backward caste ) order Act 1950 as amended by the other backward caste list of Assam, Meghalaya, Arunachal Pradesh Modification order , 1956 the Bombay Recognisation Act1960 , and Punjub Notification Act 1966. Many rural Raniaur Bania (बनिया) are village shopkeepers and money lenders. They have a state wide caste association, the Raniaur Mahasabha, which acts both as an instrument of social control as well as a communal welfare association. It should be noted that noted literary figure and one of the greatest publishers of his time Acharya Ramlochan Saran was also a Rouniyar Bania .He was the direct descendent of the last Hindu emperor of India - Hemu.Many of his surviving relatives live in India, and United States of America.for details visit at www.rouniyar.com Rouniyar Sewa Sansthan Delhi through its Founder President Subodh Kumar Gupta has been putting his hard effort to unite Rouniyars/Rouniyars across the globe. There is a similar caste of Rauniyars in Nepal though they are not affiliated to this caste sub-group. Many Rauniyar will agree with the view of Subodh Gupta, that our ancestors were belonging to different caste residing in Sasaram, Mirzapur, Bhojpur, Baksor and surrounding localities and most of them might have expressed their solidarity as warrior and joined hands with their hero Hemu, who was the Prime Minister of Adil Shah then ruler of Sasaram, Bengal, Chunar. Since Hemu lost the battle and his wife escaped from Delhi with her trusted Hindu soldiers to an unknown destination, our ancestors when returned from Panipat, started being called / termed as Raun ( battle) har ( looser). The dialect was corrupted/distorted in next few centuries to be termed as Rauniyar Bania .
According to the list of Scheduled caste ( Enclosed for Reference of Assam, Meghalaya, Monipur, Arunachal Pradesh etc ) 1950 & 1956 of Indian Constitutions as frames by the Central Government of India they listed as Bania (बनिया)& they are claim Scheduled Caste in the State of Assam, Meghalaya , Monipur, Arunachal Pradesh even in Bihar also in the year of 1985 they treated as only Scheduled Caste as Annexures II. certificate from the concern competent authority is available. list also enclosed for your reference.
In India's Few State Bania (बनिया) Treated as other backward Caste Bania have always been considered richer and civilized class of the society in post independence era even today bania are richest among all caste. So , They are choose/ claim as both as per their own Economic/ Financial Position either other backward caste or Scheduled Caste as their livelihood. Few state List Enclosed for ready reference :-
List of Assam
PART II. -Assam 1. Bansphor 2. Bhuinmali, Mali 3. Brittial Bania, Bania 4. Bhupi, Dhobi 5. Dugla, Dholi 6.Hira 7. Jalkeot 8. Jhalo, Malo, Jhalo-Malo 9. Kaibwita, Jaliya 10. 'Lalbegi II. Mahara 12. Mehtar, Bhangi 13. Muchi, Rishi 14. Namasudra I5~ Patni 16. Sutradhar.
Part XII.- Meghalaya 1. Bansphor 2. Bhuinmali, Mali 3. Brittial Bania, Bania 4. Dhupi, Dhobi 5. Dugla, Dholi 6. Hira 7. Jalkeot 8. Jhalo, Malo, Jhalo-Malo 9. Kaibartta, Jaliya 10. Lalbegi 11. Mahara 12. Mehtar, Bhangi 13. Muchi, Rishi 14. Namasudra 15. Patni 16. Sutradhar.
1[PART XX.-Mizoram 1. Bansphor 2. Bhuinmali, Mali 3. Brittial Bania, Bania 4. Dhupi, Dhobi 5. Dugla, Dholi 6. Hira 7. Jalkeot 8. Jhalo, Malo, Jhalo-Malo 9. Kaibartta, Jaliya 10. Lalbegi 11. Mahara 12. Mehtar, Bhangi 13. Muchi, Rishi 14. Namasudra 15. Patni 16. Sutradhar
2[PART XXI.-Arunachal Pradesh 1. Bansphor 2. Bhuimali or Mali 3. Brittial-Bania or Bania 4. Dhupi or Dhobi 5. Dugla or Dholi 6. Hira 7. Jalkeot 8. Jhalo, Malo or Jhalo-Malo
- People of India: Uttar Pradesh Volume XLII Part Three edited by A Hasan & J C Das page 1224 to 1228 Manohar Publications
- People of India Bihar Volume XVI Part Two edited by S Gopal & Hetukar Jha pages 817 to 820 Seagull Books
- "When will the Brahmin-Bania hegemony end?".