Inscription on the wall of Black Lion pub on Bayswater str., London, facing the Kensington park reads:
We in Moscow have inscription like that on schools, where volunteers gathered in squads to protect the capital from advancing Nazis back in 1941.
The difference between gathering in a pub and gathering in a school might be quite obvious: knowledge.
Judging by the inscription, the Black Lion customers were ready to defend the Union Jack against Napoleon Bonaparte in year 1830.
Well, the best-known Napoleon Bonaparte, called Napoleon the 1st, died in 1821, thus not posing threat to frequenters of the Black Lion. Neither could that be Napoleon 2nd Bonaparte, since, although being declared French Emperor in 1815 by his father (the 1st one), he never ruled France and in 1830 was fighting tuberculosis (loosing the fight in 1832) in his hideout in Austria.
There was also Napoleon the 3rd Bonaparte, but that guy became head of France only in 1848 and Emperor in 1852 (BTW, why do French elected heads of state tend to become Emperors?), which is in a way not exactly year 1830. In that year the 3rd one was in Italy, struggling to make a coup d’etat or something of that sort there.
All other Napoleon Bonaparts were not mature enough to frighten the Britons at that time.
In that particular year France was headed by Louis-Philippe (do not know the number, if any), who worked as its liberal monarch from 1830 Revolution to 1848 Revolution. He could pose threat to conservative Black Lion customers, but he was not Napoleon Bonaparte.
So, which Napoleon Bonaparte threatened Paddington inhabitants by invasion? Or they just needed an excuse to share their favorite ale.