Satra (Ekasarana Dharma)
Satras are institutional centers associated with the Ekasarana tradition of Vaishnavism, largely found in the Indian state of Assam and neighboring regions. Numbering in the hundreds, these centers are generally independent of each other and under the control of individual "adhikaras" (or "satradhikars"), though they can be grouped into four different "Sanghatis" (orders). These centers, in the minimum, maintain a prayer house ("Namghar", or "Kirtan-ghar"), initiate lay people into the Ekasarana tradition and include them as disciples of the Satra from whom taxes and other religious duties are extracted. Although the culture of setting up religious  institutions like Satras started in Sadiya, the Neo-Vaishnavite satra culture started in the 16th century. They grew rapidly in the 17th century and patronage extended to them by first the Koch kingdom and later the Ahom kingdom was crucial in the spread the Ekasarana religion. Many of the larger Satras house hundreds of celibate and non-celibate "bhakats" (monks), hold vast lands and are repositories of religious and cultural relics and artifacts. The Satras extend control over their lay disciples via village Namghars. Satras in which the principal preceptors lived, or which preserve some of their relics are also  called "thaan"s. Another satra was established by a king named Samudrapal at a place known as Yogihati in the same period (1232 AD) as evident from a stone inscription found in Ambari. The neo-Vaishnavite satras were established by Assamese Vaishnavite monasteries for religious practices at the initiative of the Ahom Kings of Assam in the middle of the 17th century to propagate neo Vaishnavism. Sankaradeva is said to have established his first Satra at Bardowa, his birthplace, and then in different places of Assam. Through initially the satras were started as a part of the egalitarian movement of Eksarana  Dharma, they later turned into a place of orthodoxy. From the early 20th century, the authority and orthodoxy of the Satras have been challenged by reform movements, most notably under the Sankar Sangha. The Satras coordinate some of their activities via the Asam Satra Mahasabha, an umbrella organization of all the Satras. According to the Mahasabha's count on its website there is altogether a total of 862 Satras including the satras present in both the states of Assam and West Bengal. Structures. The Satra is generally a four-sided enclosed area with four gateways ("karapat"). Centrally placed in this  enclosure is a rectangular prayer-hall ("Namghar" or "kirtanghar") at the aligned in the east-west direction. On its eastern side there is an additional independent structure called the "Manikut" (jewel-house), the "sanctum santorum", in which the "asana", a wooden tetradehral structure with four carved lions), is placed containing the main object of worship (usually a copy of the Bhagavat Purana in manuscript or an idol). The namghar is surrounded by four straight rows of huts, called "hati", in which monks ("bhakats") reside. The "adhikara" and other high officers of the Satra reside in the eastern "hatis". All structures  were originally temporary, made with wood, bamboo and covered over with thatch; brick and mortar found use after the 18th century. Monks, called "bhakats", live in satras under a "satradhikar" or "Mahanta". In some orders of the religion, the "bhakats" are celibate ("kewalia bhakat"). The satradhikar may not always be of high birth, it is recorded in many instance the satradikars belonging to tribal or lower caste origin. For eg, Mathuradasa Ata, the first satradhikar of Barpeta was from the Candal community, Narayanadasa Ata, a disciple of Sankardev was from the weaver community (Tanti) similarly Sesa, Katani, Budhbari, Chahila satras  were held by Kaibartas although they claim to be of Kayastha origin. The satras are not merely religious institutions but play cultural and historical roles in society. A dance form that was initiated by Srimanta Sankardeva and later developed within the sattras, and thus called "Sattriya", is one of the eight classical dance forms in India. Origin and evolution. The name "satra" originates in the Bhagavata Purana in Sanskrit ("sattra"), and is used in the sense of an assembly of devotees. During Sankardev's lifetime, the devotees assembled in the open, under trees. Though temporary prayer houses were built, the  tradition of devotees living in the premises did not happen during Sankardev's lifetime. The first mention of the "hati" is found in the context of the Patbausi Satra of Damodardev. Madhavdev built the Barpeta Satra, and laid down the system of daily prayer service and initiated the system of religious tithes. Vamsigopaldev was instrumental in establishing Satras in eastern Assam. The last quarter of the 16th century saw the satras divide into four different sects (also called "samhati")—Brahmasamhati, Purusasamhati, Nikasamhati, Kalasamhati. These four sects were firmly established by the early 17th century. Damodaradeva (a brahmin disciple of Sankardev) formed  the "Brahmasamhati", which represented the brahmanical practices and ritualism. It brought back the caste system to its original form but still adhered to the teachings of namadharma of Sankardev.The followers of this sect called themselves "Damodariyas" (meaning: "followers of Damodaradeva") and the "satradhikar" was chosen from a Brahmin family.It had close relationship with the Koches and the Koch king Nara Narayan was initiated into the Vaishnava order by Damodaradeva. Auniati satra, Dakhinpat Satra, Garamur satra and Kurawabahi satra became the most influential of the Brahmasamhati and received royal patronage from the Ahom kings. Caturbhuja Thakur, one of the  grandson of Sankardev headed the "Purusasamhati". This samhati practiced the original features of Sankardev teachings and therefore considered to be the main sect. The head priest was chosen either from a Kayastha or a Brahmin family. The term "purusa" is claimed to be derived from the honorific title Mahapurusa, usually applied to Sankardev. Bardowa satra founded by Sankardev remained the most popular satra of the Purusasamhati. The next samhati, the "Nikasamhati" was established by Mathuradasa and Padma Ata, both of whom were disciples of Madhavdeva. It strictly conformed to the teaching of Madhavdeva and being a purist group placed more  important on ascentism, Kamalabari Satra, Barpeta Satra and Madhupur Satra are the three centers of this samhati. The last of the samhati, the "Kalasamhati" concerned with the tribal and lowercaste societies, represented the offshoots of six sudra satra and six brahmana satra formed by Gopala Ata and his followers during the late 16th-and early 17th-centuries. The Mayamara satra and Dihing Satra, the two most important of the sudra satras admitted various local tribes into its fold — Kacharis, Kaibartas, Chutiyas, Morans, Ahoms etc. The Mayamara satra formed by Aniruddhadev (a disciple of Gopala Ata) later became the most prominent  among the six sudra satra of the Kalasamhati and revolted against Ahom kingdom during the latter part of the 18th century. The first three samhati —"Brahmasamhati", "Purusasamhati", "Nikasamhati" brought back the caste rules and Brahmanical rituals, while the "Kalasamhati" rejected caste rules and idol worship in its entirety. The Ahom kingdom initially resisted the ingress of religious preceptors it finally endorsed the Satras, enabling them to establish themselves on sound economics, make themselves attractive to the lay people, and spread the Ekasarana religion. The 17th century saw the rapid growth of the Eksarana Dharma in upper Assam and Majuli became  a focal point of Satra tradition and authority. The number of Satras grew during this period, 125 satras build in the 17th century and 85 satras build in the 18th century, while suffering two major setbacks — Moamoria rebellion and Burmese invasion of Assam. Cultural programmes. Some of the cultural programmes, which are held in Sattras: