Yep, the converters do their best to translate your save at the end of one game's timeline into a new save at the beginning of the next game's timeline. It's really cool. I say 'do their best' because different games sometimes define regions along different borders, stuff like that. Crusader Kings II might split the Iberian Peninsula up into 14 regions (just making up numbers here), while Europa Universalis IV might consolidate them a little, into 12 regions, so the converter has to recognize that. I haven't looked into it much myself, just reading the paradoxplaza subreddit and seeing people discussing it.
And yeah, it's gotta take a long time to go from 769 to 1948, but can you imagine doing that, then being able to look back at your 1100-year history and see how far you came, from a tiny barony to a modern power, fighting tooth-and-nail the entire time for survival?
And yeah, it's gotta take a long time to go from 769 to 1948, but can you imagine doing that, then being able to look back at your 1100-year history and see how far you came, from a tiny barony to a modern power, fighting tooth-and-nail the entire time for survival?