The period following the war of 1812 was called the "era of good feelings" because:
the republican party died out
federalists held political power
both parties buried their differences
all of the above
onone of the above

The actual reason is not in the option so “none of the above”.

Explanation:

The period following the War of 1812 was called the "Era of Good Feelings" because the actual reason behind the good vibes was the independence of Americans from British Empire. As they won the war and freed themselves from British, Americans were finally able to be entirely sovereign. This ignited the extreme sense of pride to all the ex-settlers , this joyful moments was considered as the “era of good feelings”.