These bold and dramatic fashion illustrations were painted in the early 1960's by Merle Bassett, one of the best known illustrators of that time. His career began in Los Angeles, studying art at Chouinard Art Institute. He found his first job for Joseph Magnin stores in San Francisco, and later Neiman Marcus in Dallas. He finally made his way to New York city where he would have a successful career as a fashion illustrator for several decades.
The illustration technique seen here uses strong black ink brushwork over a colored background that was brushed on first within the area, but not defining it precisely.
For more details on his fascinating career, you will want to read his own story, here.