[1] Stefanopoulos was born c. 1853 in Divri (now part of Olympia municipality).
He was the son of Stefanos Stefanopoulos the elder, a politician and member of the historic Stephanopoulos family.
He studied law at Athens and was married to Fani Vakalopoulou.
In the first years of his political career, he was mayor of Divri.
In 1907, he was elected mayor of Pyrgos, a position he held until his death in 1918.