Complex sentence: The Comanches sought to obtain recognition of the boundaries of the Comancheria, their homeland, while the Texians wanted the release of Texian and Mexican citizens held prisoner by the Comanches.
Split into simpler sentences: The Comanches sought to obtain recognition of the boundaries of the Comancheria, their homeland. The Texians wanted the release of Texian and Mexican captives held by the Comanches.