In 1850 he was appointed to Academy of Vienna, and painted several frescoes in the Alt-Lerchenfeld church. In 1855 he received a prize at the Paris Exposition for his painting "Charlemagne Visiting a Boys' School" and accepted nomination as professor in the Venice Academy the same year. He was a Professor of the Venice Academy from 1856 to 1866. In 1866 he returned to Vienna. His autobiography was published in Vienna in 1876. Von Blaas shared the Nazarene’s fascination with Renaissance artists and identified with their view of the religious mission of art. He became well known in Vienna social circles and painted the boy emperor Franz Joseph in 1853. Some years later he began to execute forty two-fresco paintings for the Vienna Arsenal (now the Heeresgeschichtliches Museum) from Austria’s history, which occupied him for eleven years. These are considered to be among his major works. He is the father of the genre painter Eugene von Blaas (1843–1942), whose reputation (and auction prices) has overshadowed that of his father, and Julius von Blaas (1845–1923), also a painter. He died in Vienna in 1894. Among his pupils was Francesco Beda.