It got a big boost from the grant of market privileges by Duke Albert V, Duke of Saxe-Coburg.
The first mention of Frohnlach was in the year 1260 when the founder of the Sonnefeld Monastery, Graf Count Henry II von Sonneberg, bought the village of “Otnandus de sleten” (from Kirchschletten near Zapfendorf).
Johann Stegner, the son of a construction worker, was born on 20 December 1866 in Frohnlach, District of Sonnefeld, in the Duchy of Saxe-Coburg and Gotha but he was raised in Scheuerfeld, then a village west of Coburg, in the same Duchy.
Beginning with the former Bamberger fiefs of Sonnefeld, Frohnlach and Ebersdorf, the Monastery multiplied its possessions with other properties from Bamberg, the Banz Abbey and the Benedictine abbey of Saalfeld.