The
Sword of Osman (; ) was an important
sword of state used during the coronation ceremony of the
sultans of the
Ottoman Empire. The sword was named after
Osman I, founder of the
Ottoman Dynasty. The practice started when Osman I was girt with the sword of Islam by his mentor and father-in-law
Sheikh Edebali. The girding of the sword of Osman was a vital ceremony which took place within two weeks of a sultan's accession to the throne. It was held at the
tomb complex at
Eyüp, on the
Golden Horn waterway in the capital
Constantinople. Even though the journey from
Topkapi Palace (where the sultan resided) to the Golden Horn was short, the sultan would board a boat amid much pomp to go there. The Eyüp tomb complex was built by
Mehmed II in honour of
Abu Ayyub al-Ansari, a companion of
Muhammad who had died during the first Muslim
siege of Constantinople in the 7th century. The sword girding thus occurred on what was regarded as sacred grounds, and linked the newly enthroned sultan both to his 13th-century ancestors and to Muhammad himself.