parvenu

nousukasmainen

nousukas A person who has risen, climbed up, or has been promoted to a higher social class, especially through acquisition of wealth, rights, or political authority but has not gained social acceptance by those within that new class.
2001, January 31, Francis Wheen, "The whole truth about Peter's friends", The Guardian

But the favourite's power and influence provoke intense ill-feeling among other courtiers, who regard him as a sinister, usurping parvenu with ideas above his station, or perhaps even a sorcerer.

The Progressives were of the educated middle class, angry at the rule of parvenu financiers and industrialists.

The majority of the adults, however, viewed Luisa Santiaga as the precious jewel of a rich and powerful family whom a parvenu telegraph operator was courting not for love but self-interest.