He was the second son of Ulrich IV of Hanau (born: between 1330 and 1340; died: in September or October 1380) and Countess Elizabeth of Wertheim (1347–1378 ).

In the ruling family of Hanau, an explicit primogeniture statue of 1375 stipulated that only the eldest son could inherit the Lordship and even that only he could marry.

In 1390, one of the sons of Ulrich IV, possibly Reinhard II, was enrolled as a student at the university of Heidelberg.

[1][2] Reinhard abandoned his spiritual career in 1391, and closed a contract with his elder brother Ulrich V, which guaranteed him an annual income.

The background was probably that Ulrich V's marriage was still childless and they wanted to preserve the possibility that Reinhard might succeed Ulrich V. The contract awarded Reinhard an annual sum of 400 florins and a share in the districts Partenstein, Rieneck, Bieber and Haßlau.

Under the primogeniture statute, only the eldest son was allowed to marry; consequently, the continued existence of the dynasty was under threat.

In 1391, a family contract was concluded, which allowed Reinhard II to marry if Ulrich still had no sons 10 years later.

On the other hand, Ulrich and his brothers were first cousins once removed of John II, so the ruling power remained in the family.

In 1402, their relationship became even closer and eventually, John II changed sides in the conflict the two younger brothers had with Ulrich.

The most important event of the dynastic reign of Reinhard II is his elevation to Imperial Count on 11 December 1429 by emperor Sigismund.

Some authors report that the capital was officially moved from Windecken Castle to Hanau in 1436, but no proof of this is available.

Reinhard II expanded the Late Gothic collegiate Church of Mary Magdalene and increased the number of altar priests.

The climax of this development was reached when, after the death of the archbishop in 1419, Reinhard II succeeded in recovering absolute title over the cities of Hanau and Babenhausen.

Mainz was more successful in its attempts to expand on the other side of the Main (river): in 1425, the archbishop purchased the district of Steinheim from the Lords of Eppstein.