The Rüstem Paşa Mosque, not far from the Egyptian Bazaar, is one of the hidden treasures of Istanbul. It was built by Sinan for the Grand Vizier Rüstem Paşa, who was the husband of Mihrimah, the favourite daughter of Sultan Süleyman te Magnificent. In 1561 it was finished. It houses an astounding number of tiles of the first quality of the best period. It may be a bit hard to find in the warren of streets surrounding it, to the west of the Egyptian Spice bazaar, but persevere, since you are in for a treat.

An anonymous guest contributed "Let’s deliver some historical (true) gossip:
Rüstem Paşa was a child of the ‘devşirme’ (a tax imposed on rural Christians, who had to give up some of their boys to the Sultan’s service), as was Mimar Sinan. Rüstem was the son of a Croat swineherd. A squat and ugly man, he was popularly known as the “Louse of Fortune”. Nonetheless, he was a financial wizard who successfully lined his own pockets as he guided the empire. So great was his personal fortune that at his death he left some 5000 priceless kaftans and ceremonial robes, to say nothing of lands and jewels. It is said that he even made money by selling off discarded fruits and vegetables from the imperial gardens and pocketing the proceeds. However ill-gotten his gains may have been, to them we owe some fine buildings." Curiously I had just come across the "Louse of fortune" part in the Strolling through Istanbul guidebook when it treated a medrese, by Semiz Ali Pasha, who was Grand Vezir after Rüstem and, in contrast to the latter, honest. So I think the "gossip" has the ring of truth.