In the 18th and 19th centuries many pewterers put various labels on their wares. Some were essentially advertising slogans, such as “Superfine Hard Metal” to promote the idea that the goods were of a superior quality.
Others such as “Made in London” identified where the pewter was supposedly made, but be warned: this description was applied not only by London pewterers but also by many provincial pewterers, and indeed even by some on mainland Europe. Non-London pewterers used it because traditionally London pewter was considered to be superior.
The words ENGLAND or ENGLISH PEWTER were only used after 1891, following a United States tariff law that required imported goods to bear the country of origin. An amendment of the tariff law in 1909 required the text to be changed to MADE IN ENGLAND, so any piece stamped with this is post-1909. The presence of these marks does not mean the item was actually exported to the US as many makers took the easy route and simply stamped all their wares.