Based on written records and mentions in documents, it is now possible to understand that a major settlement change must have occurred in our present-day district around the middle of the 14th century. The places (or settlement areas) of Dernbach and Monzenbach, which had been mentioned until then, are no longer mentioned from this time onward. Instead, only Seelbach is referred to, which must be the present-day village (village center). After the departure of the Dernbach knights, the people on their widely scattered farms were left unprotected. They then gathered around the already existing fortified church and formed a fortified clustered village there to protect themselves collectively against external threats.

However, more recent findings paint a somewhat different picture. The model, based on old sketches of the castle moat and excavation findings from the 1950s, likely depicts only a portion of the actual defensive structure. The terrain, as well as aerial archaeological evidence, suggests an extensive outer bailey extending to the southeast. The construction of this shared castle was probably similar to that of a motte. Therefore, it can be assumed that the small settlement area at the foot of the motte was also surrounded by a defensive structure.

Seelbach was not spared misfortune in its later history. The year 1635 brought particularly terrible times during the Thirty Years' War. First, the village was engulfed in the turmoil of war. On May 3, 1635, soldiers of Count Philipp von Mansfeld burned down the church and 89 houses. The second half of the year hit Seelbach even harder. On August 16, the plague broke out. By December 2, the Black Death had claimed 160 lives. In total, 176 people died that year; only 165 survived. The witch hunts also took their toll during this period.

Between 1629 and 1632, seven women and one man from Seelbach were executed in Herborn as witches or sorcerers. Despite the great hardship, Seelbach slowly recovered from these heavy losses.

Just a few years later, the French invaded. On their way east, Napoleon's troops also passed through Herborn-Seelbach. The troops set up camp near the village, from where they harassed the inhabitants to enforce the new French tax system, against which the people of Seelbach, in particular, resisted. Bread and livestock were stolen daily. Some Seelbach residents were forced to "volunteer" as soldiers in the French auxiliary troops. The administration was reorganized according to the French model. For the first time, Herborn-Seelbach lost its independence. It now belonged, along with Bicken, Offenbach, and Ballersbach, to the "Mairie" (mayoralty) of Bicken.

During the same years (1803-1808), the road from Burg to Bischoffen was also improved, although this road was still the old village thoroughfare (Fahlerstraße). The "new road" or "highway," between Decker's fountain and the present-day Rewe roundabout, wasn't built until the 1840s – the first Seelbach bypass! The French occupation ended in 1813. After the French were driven out, there was initially great hardship and poverty. But the village recovered.

The lime kiln in Herborn-Seelbach was also significant at that time. For a long time, three lime kilns were in operation. The economic boom was further boosted by the construction of the railway. The line from Herborn to Hartenrod was opened on February 1, 1902.

The school on Brühl, which has since been demolished, was built in 1895. However, schooling had already taken place in Herborn-Seelbach before then. The first school must have been founded between 1588 and 1594. At that time, however, classes were only held in winter and in the teacher's home. Soon, though, the "Old School" provided the necessary classrooms and a new teacher's residence. This beautiful three-story timber-framed building is believed to have been built around 1600 on the Nesselhof estate. Further archival research uncovered, among other things, a count's timber bill from 1602 for a school building in the municipality of Herborn-Seelbach.

It is therefore certain that the "Old School" was built in 1602 as a combined school and community building at its current location in the center of the village. Today, classes are held in the primary and secondary school, the "Dernbach School," which was inaugurated in 1961.

Around the turn of the century, Herborn-Seelbach experienced another outbreak of epidemic diseases. It began in 1875-76 with 12 deaths from typhus. In 1882, 26 children died of scarlet fever. This was followed by influenza (flu), typhus, measles, and finally dysentery (1918), which, despite an isolation barracks on the Gewenn hill, claimed 54 lives. In addition, Herborn-Seelbach mourned 55 fallen soldiers in the First World War.

The three Seelbach bells had to be sacrificed for the war effort in 1917. In 1919, the church tower received two new steel bells, cast by Buderus in Wetzlar. These were replaced in the autumn of 1949 by three new bells from the Rincker bell foundry in Sinn.

The church tower was renovated in 1949. The enlarged nave was consecrated in 1953. Large new housing developments were built, including those at Horch and Bitzen. In 1966, German Federal Armed Forces soldiers and American troops moved into the newly completed Aartal barracks, which were closed again in 1993 as part of troop reductions.

In 1974, a modern indoor swimming pool was finally built on the old schoolyard, but unfortunately, much to the dismay of many Herborn-Seelbach residents, it was closed again after only a few years. Connection to the Herborn city gas network promoted our continued development. A cemetery chapel and two kindergartens were also built during this period.

The former kindergarten in Adlerstrasse now serves the Evangelical Church community as a charming community center.

On January 1, 1977, Herborn-Seelbach lost its administrative independence for the second time. As part of the Hessian regional reform, our village was incorporated into Herborn.

In 1981, the gymnasium was converted into a multi-purpose hall. In 1996, we also gained a second kindergarten. In recent years, significant changes have taken place in the transportation infrastructure. The nearly 100-year-old Aar-Slzböde railway line was closed in 2001 and immediately dismantled.