"It is necessary to look into the history of the area that is now Germany to understand some of the marking on guns of the period between 1850 and 1924. I have chosen these dates for much happened to confuse us as to when and where a gun was made.
Imprints such as Prussia, Thuringia and Saxony on the water tables and barrel flats on many guns indicate that they were destined for the United States as their final destination. The U.S.Trade Laws prior to 1891 had no requirement that a country of origin be marked on product or merchandise. The Law was amended in 1891 to say that the name of the country of origin be imprinted. We therefore see Thuringia, Italy, Nippon and the like on guns of the period and up to 1921. This Trade Law was again amended in 1921 to read that the imprint must state , Made in Country of Origin. We see, then, Made in England, Made in Italy, etc.
After the downfall of Napoleon I, in 1815, European heads of state met in Vienna, Austria to reform and reorganize Europe. Parts of the Duchy of Saxony, which had previously aligned itself with the defeated French Emperor, were given to Prussia. The area also included Thiringia and the town of Suhl.The Prussian government administered the province until 1918 when the former Duchy became the Free State of Saxony. Thurginia became the Free State of Thuringia in 1920 as part of Germany. The stamping of any of these was totally to do with what year, month or day the gun was finished. It was all political, as one can see."
I lifted the above from the Winter 2005 Double Gun Journal. Hope it helps in understanding the gun's markings.
Best,
John