Nicomedia, modern İzmit, was an ancient Greek city located in Kocaeli Province. It was founded in 712 BC as a Megarian colony and was originally known as Astacus. The city was rebuilt by Nicomedes I of Bithynia in 264 BC under the name of Nicomedia and it became the metropolis of Bithynia under the Roman Empire. In the middle ages it became under Byzantine control, but following the Byzantine defeat at the Battle of Bapheus in 1302 AD, it was ruled by Ottoman beylik. In 1337 AD the city became under Ottomans Control.