Alois was born Alois Schicklgruber as his mother was not married when she gave birth to him. Five years after his birth, she married Johann Hiedler. She took to her grave the biological father of Alois Hiedler, who could possibly be the son of Johann Hiedler or there is speculation that she was with the sons of people she worked for.

Johann Hiedler had a brother Johann Nepomuk Hiedler whom after Alois Schicklgruber's success in the civil service, told him to change his last name to match his own, Hiedler, and continue the family name. However, when it came time to write the name down in the record book it was spelled as Hitler.

And so in 1876 at age 39, Alois Schicklgruber became Alois Hitler.

In 1885, after numerous affairs and two other marriages ended, the widowed Alois Hitler, 48, married the pregnant Klara Pölzl, 24, the granddaughter of uncle Johann Nepomuk Hiedler. Technically, because of the name change, she was his own niece and so he had to get special permission from the Catholic Church.