In order there to be a king, there must be land, property, or territory. The property is the king’s domain, without it the king is no king. The king needs to have territory to form his king domain or his kingdom.
Psalm 115:16 The heaven, even the heavens, are the Lord’s: but the earth He has given to the children of men.
Heaven is a real territory with a King, which is God. Earth is a real territory with a King, but He has given the dominion to the children of men. He did not give the enemy the rulership of the earth. Man did that at the Fall in the Garden of Eden. Adam rebelled against God the King of the Universe and lost the kingdom of earth and his place as king or ruler.
Jesus, the second Adam, came to earth to restore the kingdom that the first Adam lost. Now since the kingdom has been restored, all who come to Jesus and are adopted into the royal family of God can now be citizens of the Heavenly kingdom and kings and queens of the earthy realm.
The domain of earth is man’s legal right, power, authority of rulership according to Genesis 1.
Genesis 1:26 (NKJV) Then God said, Let Us make mam in Our image, according to Our likeness: let them have dominion over the fish of the sea, over the birds of the air, over the cattle, over all the earth and over every creeping thing that creeps on the earth.
When God said, Let them have dominion, He transferred the legal rights of dominion of the earth to mankind. We have authority and the power on the earth. It is a privilege not a creative right. God has creative rights to the earth, we do not. God has given us dominion and authority on earth. And He will not violate it without our permission. That is why we must ask Him to come into the earth and do things we are asking Him to do. When we do not pray, then bad things can happen because we did not use our authority against the enemy.