The first settlements in the territory of the present-day municipality of Mladenovac were established in the prehistoric period, as proved by numerous archaeological sites and around 200 remains of prehistoric settlements. The most important ones include Jablanica in the village of Medjuluzje, dating from the Iron Age and the early Roman period, Protostarcevacko site in Batasevo, dating back to the end of the sixth millennium B.C., and Divicmedj in Kovacevac, where an early medieval town from the period between 9th and 11th century was found.
Therefore, the town and villages which exist in the territory of Mladenovac today were mentioned as early as the Middle Ages, in the times of despot Stefan Lazarevic, and later, in the 16th century, in Turkish censuses as well.
The founding of Mladenovac began in 1882 during the construction of Belgrade-Nis railway. This period saw the construction of the first building of what would become the town of Mladenovac – the “Kosmaj” Inn, which has been preserved to this day, in somewhat different form. A new settlement started to develop around the railway station and the inn, on the vast marshy meadows by the little river Lug, and the pastures and fields scattered with a few village cottages. The first steam mill was constructed as early as 1885!
Mladenovac was proclaimed a town on August 2 1893 by the decree of King Aleksandar I Obrenovic. This set off sudden industrial development of the town and the settling of many craftspeople and traders. The first primary school was opened in 1895 and in 1904 the narrow gauge railway Mladenovac-Arandjelovac-Lajkovac was constructed. The construction of this railway and the passing of Belgrade-Nis railway through its territory before that, made Mladenovac a significant hub of Serbian railway traffic of the time and a big centre of the export of cattle, small stock, wheat and maize. The oldest abattoir and salami factory was set up in 1907, which marks the beginning of the industrialization of the town. In 1920 the first sack factory was established as well. Along with the commercial, craft and industrial development, the administrative function of the town developed too, so that in 1930 Mladenovac became the centre of a district bearing the same name. The district later included Kosmaj district as well.
As legend has it, the name “Mladenovac” comes from the name of Mladen, one of three brothers who came to this area 200 years after the battle of Kosovo (1389). The place where his descendants started their families was named after him. The first official records of this area were made in the Turkish census of 1528.