Ca. 1940 to 1964. The brown colour is called Iroquois and the pattern is Casual China designed by Russel Wright. If you collect mid century modern dishes, you will be familiar with the designer Russel Wright. He designed the most popular line of dishware in American history called American Modern which is widely collected. He also designed furniture which is much sought after today.
These items were found at a thrift store and I wish there had been a complete set but alas, this was all I found after scouring the store several times over.
fabfindsblog 
it’s hard to like brown stuff- so dreary – but russel wright makes even boring brown interesting. what does iroquois actually mean?
Hi reretro. I am not sure about the use of the name Iroquois for the colour. Iroquois are are a league of several nations and tribes of indigenous people of North America.
‘Iroquois’ is the China and Pottery Manufacturer (the Casual China line has many great colors). They’ve produced many restaurantware and dinnerware sets in the US (located in New York), including Pfaltzgraff…Russel Wright’s dinnerware has also been manufactured by Steubenville and now Bauer Pottery. :]
Really great thrift find!
iS ANYONE STILL CHECKING THE COMMENTS? i JUST GOT THE SET OF DISHES FROM STORAGE THAT MY MOM GOT AS A WEDDING GIFT. I ALMOST HAVE A FULL SET OF THE BROWN IROQUOIS, BUT MISSING A FEW PIECES OF THE LARGE BOWLS AND THE MEDIUM SIZE PLATES. I EVEN HAVE THE SALT AND PEPPER SHAKER WITH THE ORIGINAL CORKS. WOULD LOVE TO KNOW WHERE TO FIND REPLACEMENTS.