15th century

between 1404 and 1409	After lengthy disputes between the city patriciate on the one hand and the craftsmen's guilds and suburbanites on the other, the latter are given greater say in the council. In future, the craftsmen were able to fill some city offices from their ranks. The existence of 14 guilds is documented.
1406	There is evidence of four fishing waters on the Saale between Rasenmühle and Kunitz, which are leased to institutions and private individuals. The abundance of fish in the Saale is an important source of income. A "keulichter (from "club") tower" is mentioned (corner tower at the north-eastern corner of the town fortifications). From 1514, it is used to store gunpowder ("powder tower"). June 5: The sovereigns grant the town the "projectile privilege". All feudal dues previously due to the sovereigns are transferred to the town, which thus gains extensive financial sovereignty. The "Geschossbuch" is drawn up, providing an initial estimate of the number of inhabitants (around 2,600).
1407	The first municipal statutes (which have not survived) are confirmed for Lobeda.
1408	December 7: St. Michael's Monastery and the town council reach an agreement on the construction of the Chapel of the Holy Cross in front of the Löbdertor.
1409	The office of market master is mentioned for the first time.
1413	Construction of the town hall in its current Gothic form is completed. The main construction period of the building is between 1377 and 1380. It had a predecessor from the 13th century, individual parts of which were incorporated into the new building.
1414	May 29: The Thuringian landgraves provide the Carmelite Order with a plot of land in front of the Löbdertor for the construction of a monastery.
1416	March 29: The Jakobsspital (infirmary) for so-called "special sick", seriously or incurably ill people who pose a risk of infection, is mentioned in the northern suburb of Nollendorf.
1418	The process of founding the new Carmelite monastery is completed. There are now three monasteries in the city: the Dominican and Carmelite monasteries and the Cistercian nunnery.
1419	March 12: The association of a group of people who undertake to extinguish fires in return for a tax rebate can be considered the first "voluntary fire department" in Jena. April 21: The existence of a "women's house" (brothel) in front of the Saaltor is proven, the "Frauengasse" already appears in the 1406 land register.
1424	The choir of St. Mary's Church in Ziegenhain is consecrated as a place of pilgrimage for a miraculous image of the Virgin Mary.
1429	June 20: The sovereigns sell the upper and lower courts and the customs of Jena to the town.
1430	April 1: A house in Jenergasse appears in documents as an "alde schule".
1430/31	Fearing Hussite attacks, the town fortifications are extensively repaired and extended or partially rebuilt (construction of corner bastions, extension of the moat works, new gate towers with outer works in front).
1431	June 19: The documentary mention of a synagogue in the Leutragase is the last reliable record of a Jewish community in Jena.
1442	The first construction phase of the new Gothic Jena town church is completed. Among other things, the choir with a public passageway beneath it and the bridal portal are completed.
1446	June 20: The wedding of Landgrave Wilhelm III of Thuringia and Anna of Austria, the eldest daughter of King Albrecht II, takesplace in Jena . The "Saxon Fratricidal War" begins, which lasts until the beginning of 1451 and also leads to severe devastation in the area around Jena.
1448	May 14: The Jena Council is granted the right to strike pfennigs with the symbol of two bunches of grapes.
1450	August: The town of Lobeda is almost completely destroyed a second time after 1446 in the Saxon Fratricidal War. Burgau Castle and village and Lobdeburg Castle also fall victim to destruction.
1452	September 5-9: The famous Franciscan penitential preacher Johannes Capistran stays in Jena and preaches to a large crowd.
1457	May 16: A second weekly market is mentioned in Jena.
1462	A Jena executioner is mentioned in a document for the first time. A reference to a high court ("Galgenberg") can already be found in the 1406 Geschoßbuch.
1464	The pilgrimage church "Zu den 14 Nothelfern" is consecrated in Lutzendorf. The name of the village changes to Vierzehnheiligen by 1482 at the latest.
After 1470	Construction begins on a second town wall, built a few meters in front of the older one, about 2 meters thick and 4 to 6 meters high, which is primarily designed for the use of small arms.
1471	Construction of the Jena City Palace begins as a secondary residence for the Wettin city lords (according to a building inscription that no longer exists).
1474	Construction work on the town church of St. Michael is resumedunder the direction of the stonemason, sculptor and master craftsman Peter Heierliß (until his death in 1507). The official mill in Burgau is completed. Until 1628, it is used for grinding by the farmers of the villages belonging to Burgau.
Between 1477 and 1480	Friedrich von Lunderstedt has a late Gothic castle complex built in Lobeda - known as the "Old Castle" or "Lobeda House" - as the center of a manor.
after 1477	The offices of Jena and Burgau are combined into a double office comprising around 50 villages and jointly administered by a bailiff. He is supported in his official duties by an Amtsschösser (tax collector).
1478	August 31: "Bread benches" for offering baked goods in the town hall arcades are mentioned for the first time.
1480	June 6: The transfer of jurisdiction to the town within its Weichbild leads to the first exact description of the Weichbild. This mentions a "new bridge made of stones" over the Saale (today's "Camsdorf Bridge").
1482	The councillor Nikolaus Theuerkauf donates the St. Jacob's Chapel in front of the Zwätzen Gate near the "Siechenhaus".
1484	A double station plaque createdby Peter Heierliß bears the date 1484 (original location: in front of St. John's Church; current location: St. John's Cemetery, in front of the Friedenskirche).
1486	May 16: The foundation stone is laid for the new tower of St. Michael's.
1488	November 1: A sovereign decree ("town ordinance") confirms the participation of representatives of the community, the craftsmen's guilds and the suburbanites in the town administration, particularly in matters of account.
1490	Jena has around 3,800 inhabitants.
1491	November 2: The start of construction of the stone Saale bridge between Burgau and Lobeda is documented.
1492	December 10: A sovereign's permission is granted for a fourth fair at Aegidi (September 1) for the trade in horses and livestock.
1498	The first reference to the existence of the "Zum Bären" inn.
1499	An invoice documents the existence of the inn "Zur Sonne(n)" (also "Zur goldenen [güldenen] Sonne") in the building on the market square, the oldest parts of which date back to the 13th century.