The Stoke on Trent Museum webpage on James Sadler & Sons seems to indicate that this crinolined lady pattern was popular in the 1930s, though the backstamp evidently suggests a date of 1947+. I have other pieces of this pattern made by different companies.
The butter dish below, same pattern, is made by Lancaster and Sandland.
This is a Johnston Bros England Flow Blue, scalloped edge, dinner plate.
Flow blue is a style of white earthenware, sometimes porcelain, that originated in the Regency era, sometime in the 1820s, among the Staffordshire potters of England. The name is derived from the blue glaze that blurred or "flowed" during the firing process.
The backstamp indicates a post-1913 date of origin.
The factory was in the Charles Street works, Hanley, Stoke-on-Trent from 1883 to 2004.
Jenny found this piece in the local BSL recently. The linked article on Flow blue indicates that most English potteries stopped doing Flow blue in the mid 1910s, to the plate may date from around that period.