#OnThisDay, 12 May 1743, Maria Theresa Habsburg is crowned Queen of Bohemia and consolidates her position as the ruler of the Austrian empire. The Seven Year War was promoted by rival claims to the empire, and she worked to elevate her husband to be Holy Roman Emperor. After his death she co-ruled with her son.
She sponsored trials of smallpox inoculation, having lost three of her children to the disease.