Heaton says the whole expedition cost under $3,000, and Emily says she has big plans for ‘her’ territory.
"We’re going to help kids in Africa that don’t have food. We’re going to build a garden as big as our land," she says.
Heaton envisions an oasis of low-carbon-footprint agriculture funded by donations earned through an eventual KickStarter campaign, and even from supportive foreign governments.
But can one man establish a kingdom on foreign soil?
Edward Swaine, a professor of law at George Washington University Law School in Washington, says there could be problems.
"At a basic level, he has to be correct in asserting that this is unclaimed land... That’s not obvious to me that he’s correct," Swaine said.
"Beyond that, he has to establish effective occupation of this land beyond simply planting a flag or showing up and taking a selfie."
Heaton says he is moving towards that goal, with office space in downtown Washington and a phone number already set up. He believes that recognition is a real possibility.
"I think that once the Egyptian and Sudanese governments realize that we’re going to be a positive force for change in the area… they will realize that it’s beneficial to recognize the Kingdom of Sudan," he said, adding he hoped to soon enter talks with the two countries.
The Egyptian and Sudanese embassies in Washington did not respond to AFP requests for comment.
Even if Heaton's claim doesn’t quite stand up to legal scrutiny, Swaine says there might at least be some consolation for Emily.
"I think any little girl who declares herself to be a princess is such, and that’s strictly speaking as a matter of international law," he said, tongue firmly in cheek.
How much this will mean for Emily in the future is up for debate, but at least she seems to have received some kudos for it at school.
Her friends think her recent ascension to the rank of royalty is "cool," Emily says.