Karl von Blaas (1815–1894) was the eldest representative of a family of distinguished Austrian painters. He was born at Nauders, Tyrol, and studied at the Academy of Fine Arts of Venice. In 1837 he received the Roman prize from the Venetian Academy. At Rome he came under the influence of the Nazarenes and devoted himself to religious subjects.
He was named a professor at the Academy of Vienna in 1850. In 1855 he received a prize at the Paris Exposition for his painting "Charlemagne Visiting a Boys' School", and accepted a professorship at the Academy of Venice in the same year. He returned to Vienna in 1866 where he wrote Autobiographie, (Vienna, 1876), which contains information on his sons, Eugene de Blaas and Julius von Blaas. He produced many portraits, religious canvases, and frescoes.