and in your demeaner.
He may be the type of person who likes to be thought of as smart and powerful. He needs that image reflected back to him by those around him. That image is sustained from outside sources. A toxic environment can be created as a result.
You probably didn't provide sufficient reflection that he was seeking. Your emails were already late before they reached his inbox.
Look up "narcissistic supply". Even if your situation is not the case, knowing its existence helps.
Remember the Rules of Office: Rule #1: Boss is always right. Rule #2: When in doubt, see Rule #1. Keep this in mind when meeting your boss for the first time.