Ralcorp can trace its ancestry to 1898 when William H. Danforth of Purina Mills, which made animal feeds, began making breakfast cereal.

[4] Ralston Purina also for many years produced the familiar line of Chex and Cookie Crisp cold breakfast cereals.

In 1994, the human food business was spun off to Ralcorp Holdings, operating as Ralston Foods, which then sold its branded breakfast cereal lineup to General Mills and its Continental Baking division (Wonder Bread and Twinkies) to Interstate Bakeries.

Ralcorp manufactures many store-brand foods that are sold in grocery outlets across the United States under the retailers' private labels.

[8] The acquisition made ConAgra the largest private-label packaged food business in the United States at that time.

"TreeHouse paid $2.7 billion in cash plus transaction expenses for the business and financed the transaction through the closing of its previously announced offerings of $775 million in aggregate principal senior notes due 2024 with a 6.0% annual interest rate and common stock issuance of 13.3 million shares at a price of $65 per share (which includes the exercise, in full, of the overallotment option), aggregating $862.5 million in gross proceeds.

[11] On June 1, 2021, Post Holdings announced it acquired the ready-to-eat ("RTE") cereal business of TreeHouse Foods.