A notice indicates the Ahmediye mosque was built for Maktul Ibrahim Paşa (aka Pargalı Ibrahim Pasha, Grand Vizier of Sultan Süleyman) for the first time. It was built in the middle of the lodges for the Janissaries. For this reason it was also called the Orta Mosque (Middle mosque). After a Ahmet Fezvi Paşa quelled a riot of the Janissaries the mosque was often called Ahmediye. The building was ruined over time, and rebuilt in an octagonal shape in 1912. A fountain in its front was built for Damat Ibrahim Paşa, the last vizier of Sultan Ahmet III. Dome, minbar, rostrum and mahfil are made of wood. Under the mosque there is a Byzantine cellar.
On the web I found the first mosque was built in 1527.