The Ambrosia creamery was founded in 1917 by Albert Morris, in his home village of Lifton, on the Devon-Cornwall border, to make a rich food for infants. He took milk from local farms, where most of the cows were the Red Ruby breed, and dried it with roller dryers.
The product soon came to the attention of the British military, who took significant quantities for its soldiers, still fighting the first world war.
Just prior to the second world war, the Ambrosia creamery was the first company to start making creamed rice pudding ready in a tin. Following the outbreak of war the vast majority of production was placed in Red Cross food parcels.
After the cessation of hostilities Ambrosia relaunched the product, along with a creamed macaroni pudding.
In 1957, following increasing demand, the creamery opened a new factory near to the original production facility.
In 1990 the entire company was acquired by Colman’s ltd., a famous brand of mustard. This in turn was bought out by Unilever in 2001. Unilever sold the brand on in 2004, to Premier Foods, where it is still a core brand, alongside others such as Bisto, Branston and Hovis.
Info gleaned from Wikipedia