Division of the county
Count Reinhard III died in 1452, after reigning only a year. He was succeeded by his son Philipp "the Younger". At the time, Philipp the Younger was only four years old. This situation presented the Hanau family with a dilemma:
They could obey the primogeniture rule, which had been observed in Hanau since 1375. This would mean hoping that Philipp the younger would live to an adult age, marry and have children, who would continue the dynasty. This would have the advantage that all of the family's possessions would remain in a single hand. It would entail the risk that the dynasty might die out, if Philipp the Younger were to die without a male heir.
Alternatively, the family could ignore the primogeniture decision and allow the next agnate, Philipp the Elder, to marry. This would have the advantage of significantly increasing the probability that the dynasty continued to exist, but the disadvantage that the county would have to be divided. This model also called for urgent action, as Philipp the Elder was almost 40 years old, which was considered quite an advanced age in the 15th century.
The debate over the division of the county is relatively well documented. Two parties took shape in the country and its ruling family. Since Philipp the Younger was still a minor and his interests were represented by a guardian committee, initially consisting of his maternal grandfather, Count Palatine Otto I of Mosbach, his paternal grandmother Katharina of Nassau-Beilstein and his uncle Philipp the Elder. This committee acted as guardians and regents until the county was divided in 1458. Thereafter, Philipp the Elder acted as the sole guardian, until Philipp the Younger came of age in 1467.
Otto I was opposed to the division. He supported the interests of his daughter Margaret, the widow of Reinhard III and the mother of Philipp the Younger. He sought to position his grandson as the sole heir of the whole county.
The elderly Countess Dowager, Katharina of Nassau-Beilstein, was indifferent as to whether the line was continued via her grandson, Philipp the Younger, or via her second, son Philipp the Elder. She held that the danger of the House of Hanau dying out could be reduced by allowing Philipp the Elder to marry, since he had already proven his ability to procreate.
The supporters of Philipp the Elder organized a letter-writing campaign. Relatives of the Count and the most important organizations among their subjects — in particular the four cities in the county, Hanau, Windecken, Babenhausen and Steinau, and the associations of the Burgmannen of Babenhausen Castle and the imperial castle of Gelnhausen — as well as the vassals of the Counts of Hanau, all wrote to Otto I and requested that Philipp the Elder be allowed to marry. These letters are archived in the Hessian State Archive at Marburg.
When his daughter Margaret died in 1457, Count Palatine Otto I no longer had a reason to oppose the division. This tipped the balance in favour of dividing the country. A treaty to that effect was sealed in January 1458. Philipp the Elder received the part of the county south of the river Main, that is the district of Babenhausen and the Hanau share of Umstadt. So, the downside of a partition was mitigated by giving Philipp the Elder much less than half the county. Even so, Philipp the Elder was happy that he was finally allowed to marry, and did so later that year. In both parts, the primogeniture statute would continue to apply.
In retrospect, the decision turned out well, even if Philipp the Younger did not die childless, as had been feared. Philipp the Elder and his descendants managed to extend their county considerably through their marriages. When the last male-line descendant of Philipp the Younger died in 1642, the country was re-united under Friedrich Casimir, a descendant of Philipp the Elder.
To distinguish between the two parts of the county, the part ruled by Philipp the Elder was called Hanau-Lichtenberg after he inherited Lichtenberg in 1480. The other part was officially named Hanau-Münzenberg in 1496. In the literature, the names Hanau-Lichterberg and Hanau-Münzenberg are used to distinguish the parts before these dates, even though, strictly speaking, that is an anachronism.
