Vladimir,
Efim Grachev passed away in 1877. That means King Humbert tomato is older than 1878...
And yes, I know that Umberto I has became the King in 1878... So the history is an interesting thing. I see only one explaination in this case - Efim Grachev's Son Vladimir who has became a follower of fathers seed shop and a passion for growing vegetables, breeding and collecting seeds has got King Humbert seeds after 1878...
Dutch,
I don't know much about Victoria. It was mentioned in 1898 Seed Catalog of Vladimir Grachev along with many Burpee and Henderson vegetable varieties. Victoria tomato - red, plum shaped, very prolific according to description.
Other tomatoes there: Shah, Early Ruby, The Peach, Excelsior, Mikado, King Humbert, Wins All, Tom Thumb, Fikarazzi, President Garfield and some Russian varieties.