Ioannidis was born in the 1880s in Armenskon of Florina, then Ottoman Empire (now Alona, Greece). He started his armed actions by joining the armed group of Kottas as his adjutant and participating in the Ilinden–Preobrazhenie Uprising. He later joined the group of Pavlos Melas, assisting him and other chieftains like Efthymios Kaoudis and Georgios Tsontos who did not know the region well, acting in the region of Pelister. He set up his own armed group in 1906 cooperating with Pavlos Rakovitis, acting in the region of Florina.