Complex sentence: Musa Pasha succeeded his brother Husayn Pasha as governor of Gaza and central Palestine, but the length of his tenure is not exactly known, although a document from Jerusalem in 1670 listed him as governor.
Split into simpler sentences: Musa Pasha succeeded his brother Husayn Pasha as governor of Gaza and central Palestine. The length of his rule is not exactly known, although a document from Jerusalem in 1670 listed him as governor.