Spantidakis was born in Rethymno in 1909 and graduated Greek military school (Scholi Evelpidon). He saw action in World War II and the Greek Civil War. Eventually he rose to the rank of Lieutenant General and served as commander of the 1st Army Corps and as chief of the General Army Staff. On April 21, 1967, Colonel George Papadopoulos launched a nearly bloodless military coup in Greece. Spantidakis was named Minister of National Defence and Vice President of the government. On December 13 of that same year, after the countercoup by King Constantine II, Spantidakis - a staunch royalist - was replaced.
He died in 1996.