13th century

after 1200	The second Romanesque predecessor of St. Michael's is built, its completion can be dated to the second quarter of the 13th century.
1216	Members of a noble family named after the village of Wöllnitz are mentioned.
1218	The village of Löbstedt is first mentioned in a document.
1223	September 29: The village of Lichtenhain is mentioned for the first time.
Between 1225 and 1240	An undated document, which has been handed down in a later copy, refers to "cives" (citizens) of Jena, which proves that the village was elevated to the status of a town.
1227	Kunitz is mentioned for the first time.
1228	November 28: St. Peter's Church in Lobeda is named as a parish church with its own parish district. Chapels in Ammerbach (first mention of the town), Jägersdorf, Schlöben and (Schön-)Gleina as well as Kirchberg are assigned to it as branches.
1235	Zwätzen is listed as the seat of the district commander of the Teutonic Order of the Bailiwick of Thuringia and Saxony.
around 1237	The wooden sculpture of St. Michael, the patron saint of the church and town of Jena, is made by a carver from the Bamberg cathedral workshop.
1252	March 20: The mention of a vicar (assistant clergyman) working in Jena is evidence of the existence of a Jena parish.
1254	July 15: A municipal schoolmaster is documented. The school is located in the basement of the west tower of the town church. It changes its location several times in the following years.
1255	May 13: The village of Münchenroda is first mentioned in a document.
1257	June 1: Wenigenjena ("parvo geine") is mentioned for the first time in a document. October 31: Burgau (on the Saale) is mentioned for the first time.
1259	July 14: The village of Maua appears in a document for the first time. July 24: Ziegenhain is mentioned in a document for the first time. July 24: Jena craftsmen, Albus and Martinus Pistor (bakers), are mentioned by name for the first time.
before 1274	The office of mint master is transferred by the Lobdeburg town lords to a representative of the Jena citizenry.
1275	September 24: The first indication of the existence of a town council consisting of eight "consules Genenses".
1278	A documented legal act suggests that Franconian law prevails in the domain of the Lodeburgs.
1279	The castle "Wind(t)berg" is mentioned in documents as the seat of the Burgraves of Kirchberg. With this castle, which was probably built shortly after 1200, the two Kirchberg castles and Greifberg Castle, the Hausberg had four castles in the 13th century.
1280	September 29: The village of Drackendorf is first mentioned in a document.
1282	December 31: A Jena priest (Ridgerus = Rüdiger) is mentioned by name forthe first time.
1284	July 25: Lobeda appears in documents as a town ("civitas") for the first time.
1286	The Dominican monastery - located at the north-west corner of the town - is founded.
1288	The oldest surviving copy of the town seal is attached to a document from this year.
1298	The paper mill at the entrance to the Mühltal valley is mentioned (as the "Nasenmühle").
Between 1290 and 1300	The Wettins acquire a quarter of Jena by marriage from the Lobdeburg line of Arnshaugk.