Complex sentence: Te Rauparaha was then released as he was sick and the government became the owners of much of the unsold land in the Wairau Valley when Te Rauparaha gave up his claim.
Split into simpler sentences: Te Rauparaha was then released as he was sick. The government became the owners of much of the unsold land in the Wairau Valley when Te Rauparaha gave up his claim.