Dumal
Dumal, also called as Dumala (also known as Nanda Gaudas in eastern Odisha), is a community found mostly in western Odisha, India. This caste is categorised as an Other Backward Class according to Reservation system of India. Origin
They were the Nanda Gaudas(Gopalas) of Puri. Their role was to supply milk, curd and ghee to the temple of Lord Jagannath in Puri. One day, a vulture was found sitting on the Neelachakra of the temple. The puja panda(priest) had a dream and came to know that the ghee served was impure, for which Lord Jagannath was dissatisfied and thus Vulture appeared. The puja panda secretly informed this to the Gajapati Maharaja and the King ordered punishment. One official from the court secretly informed the Gaudas about kings decision to punish them next day. That night the innocent Gaudas who supplied Ghee to the temple, left their houses in Puri with their families to save themselves and went towards west. For many days the King and his men chased the Gaudas. After many days of tireless escape, they finally got out of the kingdom and reached the village Dumbagarh of Athamallik in the Kingdom of Boudh. Thus, in course of time, the Gaudas came to be known as Duma Gaudas and later as Dumal. Occupations and contributions
The people of Dumal caste played an important role in the agricultural sector in the past. They brought effective changes to farming which led to rise in food surplus of the kingdom of Boudh. Due to heavy concentration of dumals in Boudh, the King of Boudh was known as Dedha Lakhya Dumbadhipati or the King of one and half lakh dumals. In his daughter's marriage, the King of Boudh gave one dumal family along with four Kulta family to the King of Patna as an invaluable dowry to help Patna Kingdom deal with grain shortages by implementing better farming methods. The dumal family played a significant role in developing the agricultural production of the Patna Kingdom (erstwhile Balangir, Sonepur, Sambalpur, Raigarh, Bamra). In course of time, due to their huge contribution to food security, the dumals were given vast area of lands for cultivation to meet the food demand of the kingdom. They vastly increased the lands under cultivation by clearing forests and gradually with rising wealth and power the Dumals became the zamindars of villages. The dumals had high responsible posts in the courts of Boudh, Patna, Sonepur, Redhakhol, Bamanda and Bamur Kingdom. Culture and festivals
Aswina month is the important month for Dumals with regards to festivals. They worship Sthambeswari or Khambeswari (Maheswari) as their presiding deity on the full moon day in the month of Aswina (September-October). On this auspicious day for Dumal community they offer puja known as Mahakhala puja with Maleswari song. They worship Brahmanarayani, Thakurani, Parameswari in the north-east corner of a dark room. Many Dumals worship Nisan baja (semi-circular drum with the sticks). During fairs and festivals they first worship this drum and then perform other worships. The males perform Badi Khela (Maheswari Badi) in the month of Aswina in front of the Goddess Maheswari. The Badi khela is played with weapons(sword, mace etc) shaped wooden sticks, which indicates their role as a martial race in the past. They sacrifice goats, sheep for other deities in the temple of Maheswari. But Godess Maheswari is propitiated with milk, ghee, curd, fruits, etc. References

Further reading 

Social groups of Odisha
Other Backward Classes
Indian castes
Ethnic groups in Odisha