Bayezid Pasa was built during the mayoralty Bayezid Pasa in Amasya in 1414, prior to his appointment as grand vizier by Mehmed I (1403-1421). The pasha acquired a large number of windmills, agricultural land, gardens, stores and public baths in the area to provide income for the religious endowment or waqf (vakif) responsible for the operation and maintenance of the mosque.
Oriented 10 degrees to the east of south, the mosque consists of five-bay portico and a central hall flanked by rooms to the east and west and a qibla iwan projecting south. The portico is domed with square columns; the inner surface of each dome features a different decoration including two swirls and a sixteen-sided star. There are two ornamental basins carved into the portico floor. The entryway is set in a tall vaulted vestibule and crowned with an elaborate muqarnas. Balconies connected to the upper-level rooms open onto this vestibule and onto the portico façade protected with carved wooden balustrades. The foundation plaque is in Arabic and wraps around the entryway. The name of the architect or builder, Ebu Bekir bin Mehmed Museymes of Aleppo, is found next to the foundation plaque and above the western portico arch. The names of architect Yakup bin-i Abdullah and builder Zeynettin bin-i Zekeriya, are inscribed on the central portico piers in association with the 1419 repair. A later plaque, found on the qibla wall, commemorates the 1887-88 restoration.
Inside, the domed central hall gives access to six rooms: four large rooms to the east and west and two narrow cells flanking the entrance. The large rooms, once used by dervishes, are equipped with plaster furnaces and shelving. They are domed, with two small lanterns atop the two northern domes. A staircase placed between the two western rooms leads up to two rooms along the portico wall and to the minaret, which rose above the portico. It also gives access to latrines at the basement level, a feature unique to this mosque.
The central hall is extended with a smaller iwan to the south, separated by a grand arch. The iwan dome is carried on muqarnas pendentives and sits slightly lower than the central hall dome, which is crowned with a lantern. There are eight windows - some blind - on each dome, although light comes in primarily from the fourteen windows pierced into the iwan walls. The mihrab is raised on a marble podium and sits at the center of a large stone frame filled with geometric carvings. A carved panel with interlocking stars and dodecagons adorns the mihrab niche, which is crowned by a muqarnas vault and flanked by two bulbous columns of red and green stone. The plastered interior is plain with the exception of stone cornices and shallow decorative archways carved into the walls.
The decorative effort on the exterior is focused on the portico. The portico arches, assembled of red and white marble voussoirs, are framed with a dark red stone band carved with arabesques. A second band of red stone is inscribed with a list (vakfiye) of the properties endowed to the mosque. It is topped by a thick band of interlocking stars and octagons and a muqarnas cornice. A cornice of green stone envelops the building above the casement level, separating limestone (küfeki) construction from alternating rows of limestone and brick above. A saw-tooth brick cornice caps the walls and the drums of domes. The four original windowpanes inside the mosque, and the walnut mosque door are valuable examples of period woodworking.
The soup kitchen (imaret) and guesthouse were replaced by modern buildings of the adjoining military zone, which has incorporated a large part of the historic cemetery into its grounds. Only a part of the spiral stairs remains from the original minaret.
Ayverdi, Ekrem Hakki. Osmanli mi?mârisinde Çelebi ve II. Sultan Murad devri, 806-855 (1403-1451): II, 4-25. Istanbul: Baha Matbaasi, 1972.