No Person except a natural born Citizen, or a Citizen of the United States, at the time of the Adoption of this Constitution, shall be eligible to the Office of President. ~ U.S. Constitution, Article II, section 1If Ted Cruz is elected president then he would be the first president in American history born outside the boundaries of the United States or the British colonies that formed the United States at its founding. That doesn't mean there haven't been many claims made by presidential opponents that their births are questionable.
That leads us to the first true birther attack. His opponents charged Andrew was actually born aboard the boat and is therefore not a "natural born citizen." Of course, Jackson was a citizen at the adoption of the Constitution in 1787, so that charge is meaningless.
A South Carolina newspaper described Lincoln as "a lank-sided Yankee of the uncomeliest visage, and of the dirtiest complexion." Political cartoons would characterize Lincoln as a monkey. Even today white supremacists attack Lincoln with the N-word.
Chester Alan Arthur
Another pure birther attack. Arthur was picked as Garfield's vice-president purely because of his connection to the corrupt
Roscoe Conkling machine in New York. Arthur's family had a vagabond life around Vermont in the 1820's, mostly because his father's rabid abolitionist views kept getting him fired.
Opponents of Arthur charged that, during the family's travels, Chester had been born while his family had been across the border in Canada.
Barry Goldwater was born in territorial Arizona three years before it became a state. There was no serious question that this was disqualifying although it was mentioned occasionally.
George Romney was born in Mexico of parents who had been born in territorial Utah. Legal scholars said it was a non-issue. It never got a chance to be seriously discussed because Romney dropped out of the race before any delegates were selected.
John McCain was born in the Panama Canal Zone and received a congressional resolution declaring him constitutionally eligible.
And Now Cruz
For two hundred years courts have avoided defining who is eligible to be president. They consider it a political matter to be decided by legislators or voters. They won't touch the Cruz question.
Cruz most closely resembles George Romney's case. His family voluntarily emigrated from the United States with the intent of permanently living in a foreign country. Romney's family only returned to the US as refugees from the violence of the Mexican Revolution. Cruz's family only returned to the US as economic refugees because they couldn't make it in Calgary.
Both of Romney's parents were American citizens and neither became Mexican citizens. Only one of Cruz's parents was an American citizen and they both became citizens of Canada. George Romney was never granted Mexican citizenship. Ted Cruz was a legal citizen of Canada from his birth until he renounced it in 2014.
Is Cruz a natural born Citizen?
Legally, probably yes. Politically, probably no. The fact that he has held duel citizenship for almost all of his life makes Cruz, at best, a dangerous precedent. What if the next duel citizen candidate has more loyalty to his birth country than his adopted country?