Complex sentence: The first stage in construction of the mosque started in 1597 with a decree by Safiye Sultan, the wife of Sultan Murad III. The original architect was Davut Aga, an apprentice to the great Mimar Sinan.
Split into simpler sentences: The first stage in construction of the mosque started in 1597. It was ordered by Safiye Sultan, who was the wife of Sultan Murad III. The original architect was Davut Aga, an apprentice to the great Mimar Sinan.