Jember as an administrative city with the majority of its people are farmers. Based on the investigation of many historians who stated that the city area of ​​Jember was formerly an area of ​​trade crossings in the era of the Lamajang Tigang Juru kingdom to Bali. After a year had passed since the expulsion of the Tartar Mongolian warriors from the land of Java, referring to the Harsawijaya Song, in "Sumenep Agreement" on November 10, 1293 AD, Raden Wijaya (son-in-law of Kertanegara Singosari) was crowned King of Majapahit whose territory initially covered Malang and its surroundings (the former kingdom of Singosari), Pasuruan, and areas in the western part while for the eastern region stood the Lamajang Tigang Juru kingdom led by Arya Wiraraja (Banyak Wide, Adipati ing Songenep) which later in Lumajang folklore is referred to as King Menak Koncar I. The Lamajang Tigang Juru Kingdom itself controls the Madura, Lamajang, Patukangan or Panarukan and Blambangan areas. From the division of the territory of the former Singosari Kingdom, we recognize that there are 2 different cultures in East Java, where the former Majapahit kingdom is known to have Mataraman culture, while the former royal territory of Lamajang Tigang Juru is known as "Pendalungan culture (a mixture of Javanese and Madurese)" around the area of ​​the present Horseshoe area. King Menak Koncar I (Arya Wiraraja) reigned from 1293 to 1316 AD. After King Menak Koncar I (Arya Wiraraja) died, replaced by his successor viz Mpu Nambi was attacked by Majapahit which caused Lamajang Tigang Juru to fall and the death of Mpu Nambi who is also the governor of Majapahit (Lamajang Tigang Juru of the Majapahit fief as a reward for Arya Wiraraja's services on the Songenep agreement). Babad Pararaton recounts the downfall of Lamajang in the Hinduism Saka year "Naganahut-wulan" (mean; The dragon bites the moon) and in the Babad Negarakertagama mentioned year "Muktigunapaksarupa" both of which show the year 1238 Saka or 1316 AD. The fall of Lamajang made its port cities such as Sadeng and Patukangan put up a resistance which came to be known as "Pasadeng" or sadeng and ketha war in 1331 AD.

Some historians have an analysis based on trade routes and historical artifacts that the center of Blambangan culture is around South Jember (more or less the position around gumukmas and its surroundings). This is due to the discovery of the ruins of the Deres Temple RT.01 RW.03 Krajan Hamlet, Purwoasri Village, Gumukmas District, Jember Regency, based on the archives of Dutch minutes - Notulen van de Algemeene en Directievergaderingen van Het Bataviaasch Genootschap van Kunsten and Wetenschappen 1900 AD. But all of them require more in-depth research to be able to trace history with certainty.

In the last few decades, Jember as an administrative city has moved forward in all fields. Physical development marked by the opening of the Notohadinegoro pioneering airfield as well as the many national achievements made by its young people in all professional fields, including entertainment, politics, trade and active service. One of the achievements at the local level was the inauguration of the new commander of the 0824 Jember military district, Lt. Col. Inf. Rahmat Cahyo Dinarso. He is a native of Jember, to be precise, in the Kalisat sub-district, Jember Regency, graduated from the Military Academy in 2003, who previously served in the presidential security force. Graduated from SMAN 1 Kalisat in 1998 and has served in many assignments to Papua.

Kalisat 1st Senior High School which was founded in 1983 has produced a young generation of achievers both in police and military service, academics to government officials. The 1998 batch of alumni who are members of the Sahabat'98 activity are a common forum for participating actively, contribute to religious activities, people's economy, culture, social, as well as defense and security in the Jember region and its surroundings especially in the sub-districts of Kalisat, Mayang, Sukowono, Sumber Jambe, Ledokombo, etc. Hopely that this forum can develop widely not only exist in that area but can establish friendly relations with other regions.

One of the other achievements recorded and made the good name of the city of Jember in other cities is the inauguration of the commander of the 0818 Malang military district, namely, Lt. Col. Inf. Taufik Hidayat, who is also an Kalisat 1st Senior High School alumnus, Jember Regency, class of 1998, is native from the Jember area. There have been many of his assignments in other areas such as in Aceh, and others. The young people in Jember should be proud of these achievements even though it's a bit of a story from the stories of other great achievements of Jember children, are expected to bring a message of hope and enthusiasm to emulate them in other professional fields, to always be creative, innovate so that it has an impact on the progress of the region of origin.

With the slogan Jember Terbina, Jember Orderly, Clean, Beautiful and Comfortable accompanied by the motto "Carya Dharma Praja Mukti, Work and serve for the nation and the state interest" the city of Jember is increasingly advanced, developing into a big city and polite in its morals. (posting date: 29/03/2023, Darmawan) source: www.sahabat98-kalisat.com.