YOU SAID:
I'm the king of the world!
INTO JAPANESE
おれは世界の王である!
BACK INTO ENGLISH
I, the King of the world!
INTO JAPANESE
私は、世界の王!
BACK INTO ENGLISH
I was the King of the world!
INTO JAPANESE
私は、世界の王だった!
BACK INTO ENGLISH
I was the King of the world!
That didn't even make that much sense in English.