The company has five wholly owned divisions, which include Chemical Intermediates and Solvents, Composites, Industrial Specialties, Personal and Home Care, & Pharmaceuticals, Food and Beverage, and Agriculture.

One mile south of the city of Catlettsburg, the site contained an existing refinery which was purchased by Blazer which had been in operation since 1916.

The Catlettsburg site was advantageous due to its location near the Ohio River and offered an efficient means of transportation for the fledgling company.

With funds supplied by Swiss Oil, Blazer arranged to buy, at a price of $212,500, the small unprofitable 1,000 barrel per day refinery of Great Eastern Refining Company which had been owned by coal operators in Huntington, West Virginia.

[5] On February 2, 1924, Blazer and three Swiss Oil executives incorporated Ashland Refining Company, with a capital of $250,000.

Blazer supported creative arts and invited nearby Greenup County educator and internationally acclaimed author Jesse Stuart to open each annual meeting with a story, a poem, or a bit of humor.

[6] By 1953, Ashland Oil and Refining Company had 3,518 miles of crude oil pipelines, 252 miles of product lines, six refineries processing an average of 124,000 barrels a day, operated nine tow boats on the inland waterways, and owned over 100 barges.

In 1969, the company reorganized to form Ashland Petroleum with Robert T. McCowan as its first president,[11] as well as entering into a joint venture in Coal mining under the name Arch Mineral.

With revenues of $3.4 billion, the Ashland Distribution business had approximately 2,000 employees across North America and Europe, and entered the China plastics market in 2009.

[23][24] In May 2011 Ashland announced that it had bought the privately owned company International Specialty Products, Inc. (ISP) for $3.2 billion.

[25] In 2014, Ashland Water Technologies was sold to a private equity fund managed by Clayton, Dubilier & Rice.

[27] In January 2019, Ashland struck a deal with activist investor Cruiser Capital Advisors, which had planned to mount a proxy fight to replace four board directors.

Instead, the two parties reached an agreement involving a consulting role for one of Cruiser's director nominees and more input regarding future board appointees.

[28] In October 2019, Ashland announced Guillermo Novo would succeed William A. Wulfsohn as chairman and chief executive officer.