In Europe, Blankenship sang roles at the opera houses in Vienna (Vienna Volksoper & Vienna State Opera), Stuttgart, Hamburg, Braunschweig (1957–1960), Bern (1960), Mannheim, Brunswick, Munich (from 1965), Berne, Klagenfurt (1956 European debut), Bregenz (1972 as Phoebus in The Fairy-Queen by Henry Purcell). In the United States, he sang with the Santa Fe Opera, San Antonio, San Diego (1968), Dallas Opera, and Houston Grand Opera. He has sung in international festivals in Moscow, Salzburg, Vienna, Munich, and Rio de Janeiro. He has concertized with major orchestras on radio and television.
- LP – Amadeo AVRS 5038, Philips SAL 3498 (1965) (LCCN 98-708397); Amadeo AVRS 13 257
- CD (re-release) Vanguard Classics (1994)
- William Blankenship (Max), Evelyn Lear (Anita), Gerd Feldhoff (Jonny), Thomas Stewart (Daniello), Lucia Popp (Yvonne)
- Vienna Volksoper Orchestra, Vienna Academy Chamber Choir, Heinrich Hollreiser, conductor
After a year at the University of Texas at Austin, Blankenship, in 1947, won a three-year scholarship to study with Mary McCormic at the University of North Texas College of Music, where in 1950 he earned a Bachelor of Music degree. While an undergraduate at North Texas, he sang major opera roles with the school's Opera Workshop directed by Mary McCormic. After three years in the Air Force (1950–1953), he attended the Juilliard School (1953–1955), studying voice with Mack Harrell and Povla Frijsh.
In 1954, Blankenship was selected by Mary Garden for the National Arts Foundation's operatic fellowship, which included a $1,200 stipend and promise of engagements in leading opera houses of France and Italy. Garden, who had auditioned 300 young American singers said that Blankenship was the finest tenor voice she had heard in America. The fellowship included a tour of study at the Vienna Academy of Music from 1955 to 1956, where he earned an opera diploma.
- "Texan Sings in Vienna and Hopes U.S. Will Call", New York Times, December 13, 1964
- The New Grove Dictionary of Opera (Blankenship is in vol. 1 of 4), Stanley Sadie (ed.), New York: Grove's Dictionaries of Music (1992); OCLC 26809899
- Who's Who in Opera, An international biographical directory of singers, conductors, directors, designers, and administrators, by Maria F. Rich (ed.), New York: Arno Press (1976); OCLC 2341204
- "William Blankenship", Oxford Music Online, (2007 & 2011); OCLC 230202868
- "Operatic Grant to Blankenship", New York Herald Tribune, March 31, 1954
- "US Doesn't Offer Enough Opportunity, Singer Says, So He Sings in Europe", Denton Record-Chronicle, March 11, 1960
- "NT Will Honor 3 Persons as Distinguished Graduates", Denton Record-Chronicle, October 24, 1971, pg. 9A