If something on a united kingdom website says a container holds 3 measures of milk how much is that in standardized units?
An imperial gallon used to be used in the United Kingdom and all Commonwealth nations. Even though these measures were superceded by the metric system, vestiges of this measuring system still exist. Primarily in cooking and fluid measures. Englishmen still visit the pubs for dragms and pints of their favorite beverages. These are measures related to the imperial gallon.
The Roman Kingdom ended in 509 BCE. The way the Roman Kingdom fell was because King Tarquin II was ousted by aristocrats because of the centralizing measures undertaken by the monarchy. The aristocrats felt that the Kingdom was corrupt and needed to be replaced by a more just and fair system, creating the Roman Republic.