Born March 15, 1767 and therefore was grandfathered past the NBC requirement as he was a "a citizen of the United States, at the time of the adoption of this Constitution". Constitutionally Qualified.
"Presidents with one immigrant parent are:
President Thomas Jefferson (1801-1809), whose mother was born in England,"
Born 13 April 1743 and therefore was grandfathered past the NBC requirement as he was a "a citizen of the United States, at the time of the adoption of this Constitution". Constitutionally Qualified.
"President James Buchanan (1857-1861) Irish father"
His mother Elizabeth Speer was born in Pennsylvania. His father James Buchanan emigrated to the United States from Ireland in 1783. Before the Constitution, United States citizenship was conferred on citizens by the States. When the Constitution was ratified, each citizen of a state became a citizen of the United States. No formal naturalization was needed.
On June 21, 1788 the Constitution was ratified. The Buchanans were citizens of Pennsylvania and therefore James Sr. was a citizen of the United States. When James Jr. was born in Pennsylvania he was therefore a natural born citizen, born on United States soil to two US citizen parents. Constitutionally Qualified.
"President Chester Arthur (1881-1885), Irish father"
The first usurper POTUS, who's father didn't naturalize until he was 14 years old. Told many lies about himself, ordered many of his papers burned upon his death. His non NBC status was not known by the public at large prior to or during the election nor while he was in office. Constitutionally unqualified.
"President Woodrow Wilson (1913-1921) Mother born in England"
Wilson’s mother was from Carlisle, England. His father was a US citizen from Ohio. Wilson’s mother gained US citizenship when she married his father according to a congressional Act of February 1855, which stated,
“any woman who might lawfully be naturalized under existing laws, married, or shall be married to a citizen of the United States, shall be deemed and taken to be a citizen.” [Act of February 10, 1855, 10 Stat. 604, section 2]
This was called derivative citizenship. This act was enacted in 1855. Woodrow Wilson was born in December 1856. He was born in the US, both parents were US citizens - natural born citizen. Constitutionally qualified.
"President Herbert Hoover (1929-1933), Mother born in Canada."
Hoover was born in Iowa, 1874. He was the 31st President. His father Jesse was from Ohio, a US citizen. His mother Hulda Minthorn was from Ontario, Canada. They were married in 1870. According to the 1855 act, which was in effect until 1922, Hoover’s mother became a US citizen automatically when she married Jesse.
So, Hoover was born in the US, both parents were citizens - natural born citizen. Constitutionally qualified.
so as long as you are married to a US citizen then you are a natural born citizen. (this NBC stuff is just clouding the issue with NBC the network)
Even so, you have shown there is at least on prior serving president who without dispute had one parent who was not a US citizen.