The first of eight brothers, Nikolaos was born to Avgerinos and Kyritsa in the village of Kapourna near Makrynitsa, on Mt Pelion, during the era of Ottoman rule. Due to financial necessity, the family moved to another village, and from there when he was 12 years old, Nikolaos went to the city of Velestino, to work in a store belonging to a relative. An Ottoman customer saw Nikolaos' intelligence and aptitude and wanted to take him to work in his harem. Nikolaos' uncle repeatedly refused, but finally the child was taken by force.
About a year later, Nikolaos' father went to get him back, but the Ottoman managed to keep Nicholas, saying that when his own son returned from the war, he would free Nicholas. When the Ottoman's son returned from the war, he proposed to convert Nicholas to Islam and keep him. They succeeded in convincing him, and he agreed to be circumcised; his name was changed to Ibrahim.