There are many overseas players at lishogi, and many of them have the same skill level as high-ranked players in Japan. This really surprises me.
Many shogi books are written in Japanese. Although some books have been translated, overseas players should have less information available than Japanese players. However, for some reason there are oversea dan players in lishogi, and they are quite high ranking players.
I was very surprised when an overseas player wrote a study about komaochi (piece handicap opening) because nowadays few Japanese players know about komaochi's opening. I find this very strange.
I want to know why they are so knowledgeable and strong at Shogi.
Why are non-Japanese players so good at shogi?
Well, because we like shogi, and we have a community of players who help each other get better at the game.
Some of them might understand Japanese so they can use Japanese resources
Japanese isn't necessary at all to become a dan level player. The resources we have in English can sufficiently get you to 1-dan with enough dedication to playing, even moreso if you regularly interact with other shogi players and ask questions often.
There's a lot of good answers here, but also I think that anyone who's played Western Chess already has a good grasp of the essential concepts (tactical ideas, checkmates, pinned pieces, etc), and it's just a matter of adjusting to the pace and structure of shogi and its pieces. For example, I could imagine that a high-level Western Chess player - I'm thinking IM rank or so - could achieve a 1-Dan rank in shogi with relative ease, if they wanted to.
I think it's really about learning the concepts. And those are pretty abstract, and not dependent on Japan or anything Japanese, specifically. I have a couple of shogi books at home, and a few of them are completely in Japanese despite me barely understanding Japanese. Yet I don't have much trouble working through them, as I can just read the notation and the few short sentences that I DO understand, make the moves on the board, and simply see what's happening.
not sure if my opinion would count here, as I don't truly know my own rating.
Hidetchi's youtube videos really helps get you from ground level to having a fair understanding of the basics along with some of the more advanced concepts; also, being willing to experiment and being ok with the outcome of said experiments. see, losing a game will only affect that game, but learning from that game will affect the ones to follow
Never underestimate the power of "What? I lost? Oh, heeeeeell no!"
Can someone tell me: Which lichess rating corresponds (approximatly) to dan-level?
I'm definitely not qualified to speak here, as I am a very weak player who started playing shogi with his grandfather for fun, but here's my two cents. Papermask said this once, but I'll say it again because it's very true; YouTube videos, especially Hidetchi's, really help with the basics. If you haven’t gotten into shogi from chess or have a hard time getting used to the basics of shogi, definitely check Hidetchi out. And I suppose playing with the AI helps, but playing with real people greatly increases your knowledge in terms of human moves and traps. I highly recommend practicing Tsume every day, as they are relatively easier than regular puzzles. If you are brand new, I also recommend starting off with bullet games so that you can get used to the movements of the pieces and find good moves through trial and error. I hope this helped.
We have some shogi books translated into other languages that gives us more abilities to understand the secrets of playing shogi and there are some videos on Youtube where you can see some games of shogi, not only the rules. The second reason is that shogi pieces are similar to chess pieces in moving and capturing and strong chess players can realise how they should play shogi (you know how pieces move – you know how you should create tactics in the game). Shogi has practically endless variations versus 10^120 ones in classic chess that makes shogi very attractive. The main reason why non-Japanese players are as strong in shogi as the Japanese one is practice: more puzzles + more games = excellent experience of playing