Likely the product of meat rationing. Although these casseroles proliferated in the 1960s, rice casseroles as a category start appearing in (paywall-locked, sadly) newspapers in the 1940s.
|A family recipe provided by Jennifer Kiel of Washington, DC, from her mother-in-law’s collection, started in Kent, Ohio.|
Aunt Mae’s Rice Casserole
1 lb. fresh pork, cut in small pieces
Brown in a skillet.
1 cup onions
1 cup celery
1/2 cup uncooked rice, scant
1 can mushroom soup
1 can chicken soup
Some liquid will be needed.
Combine all the above and bake at 350 degrees for 1-1/2 hours. Serves six.