Rosemann of Isenburg-Kempenich was a Lord of Isenburg-Kempenich co-ruling with his brothers Salentin and Theodoric II, and eventually his nephew Theodoric III. Rosemann was a son of Theodoric I of Isenburg-Kempenich who co-ruled with his brother Florentin. After the death of his father and uncle, Rosemann and his brothers became the lords of Kempenich. Salentin, the eldest, became the most important of the three brothers, but after his death sometime after 1213 Rosemann became the senior member. Rosemann was mentioned in documents as late as 1255, and he used his close relation to the powerful counts of Virneburg and Isenburg-Grenzau to improve the standing of Kempenich.