Complex sentence: Matilda's power was considerably augmented by these deaths; she was now the undisputed heir of all her parents' allodial lands, but it seemed unlikely that Henry would formally invest her with the Margraviate.
Split into simpler sentences: Matilda's power was considerably augmented by these deaths; she was now the undisputed heir of all her parents' allodial lands. It seemed unlikely, however, that Henry would formally invest her with the margraviate.