The
Siege of Trebizond was the successful siege of the city of
Trebizond, capital of the
Empire of Trebizond, by the
Ottomans under Sultan
Mehmed II, which ended on August 15, 1461. The siege was the culmination of a lengthy campaign on the Ottoman side, which involved co-ordinated but independent manoeuvres by a large army and navy. The Trapezuntine defenders had relied on a network of alliances that would provide them with support and manpower when the Ottomans began their siege, but failed at the moment Emperor
David Megas Komnenos most needed it.