This is a really nice example with a Damascus steel blade. From the time of George V whose reign ended in 1866 after the battle of Langensalza. It has the GRV cypher on the guard and on both sides of the blade.
The general in the postcard on the left appears to be carrying one of these. Perhaps it was carried at Langensalza, Hannover's last hurrah before being absorbed into Prussia. The medal commemorates the battle. I think the receiver's name is on the side.