Cool Forgotten Chess Things

Hey guys, I was just really curious if anyone here knew any weird and obscure chess rules that died out over the years or where canceled?

The rules of Chess have been pretty stable for about 500 years.  There have been occasional regional variations or medieval innovations that didn't catch on everywhere.  In India, the two square opening for pawns never caught on, which is where we get the "King's Indian" opening.  I've known some Arabs who were startled the first time someone they were playing against castled.  Apparently, the "street rules" in some placed didn't pick up that innovation.

As for neat moves that existed in medieval variants that eventually died out, my favorite comes from Tamerlane's Chess, known from two surviving manuscripts from the court of Tamerlane.  It is translated as a "ransom move".  Once per game, when the king is in check, the player can swap positions of the king and any other piece of his choice.

Also from Tamerlane's Chess, a pawn promotes only to a specific piece type.  There is a "pawn of knights", that promotes to a knight, and a "pawn of rooks" that promotes to a rook.  The interesting one is the "pawn of kings".  It promotes to a "prince".  If the king is subsequently captured, the player does not lose the game if he has a prince in play.  Instead, the prince inherits the throne.

Not forgotten in tricky chess puzzles, but no longer legal in a game ... pawn promotion under the old rules! It didn't specify which color you promote into! Some well-known puzzles involve things like White promoting a pawn into a Black piece for checkmate, since Black can't capture their own pieces

The weirdest of all is the "pawn of pawns".  When it gets to the back rank, it stays there and cannot be captured.  However, if there is a situation on the board where a pawn could fork two pieces, the promoted pawn of pawns moves to that spot.  Now, not only is he likely to be able to capture a piece, but if he once more manages to make it to the back rank, he promotes to an "adventitious king".  This piece behaves like a king or prince, i.e. it moves like a king, and the game isn't over as long as there is any king, prince, or adventitious king.

In several different variations of the rules, I've seen a lot of disagreement over the exact rules related to the pawn of pawns.  I can only suspect that the two manuscripts differ slightly and/or that the translation is a bit tricky.

There's one more thing.  The board (which I think is 11x10) has two special squares, appended to two ranks, one near each side.  This is the "citadel" square.  If you move your own king into an enemy citadel, you can declare the game a draw.  No piece can move into your own citadel......except an adventitious king.

Somewhere on chess.com, there's a thread by me entitled "I finally won a game of Tamerlane's Chess", describing my play against a computer, although the web page where I linked the annotation is now dead.  I've played two games of it "over the board", both at events of the Society for Creative Anachronism.  

well... no forgtten chess rules that i know but this move is widely missed by beginers and infurates me.

extremeley ignored for lower rateds.

Very interesting chess history piece from MeadMaker: "As for neat moves that existed in medieval variants that eventually died out, my favorite comes from Tamerlane's Chess, known from two surviving manuscripts from the court of Tamerlane.  It is translated as a "ransom move".  Once per game, when the king is in check, the player can swap positions of the king and any other piece of his choice.

  "Also from Tamerlane's Chess, a pawn promotes only to a specific piece type.  There is a "pawn of knights", that promotes to a knight, and a "pawn of rooks" that promotes to a rook.  The interesting one is the "pawn of kings".  It promotes to a "prince".  If the king is subsequently captured, the player does not lose the game if he has a prince in play.  Instead, the prince inherits the throne."

Also, in connection with MeadMakers point in response to Aadarshlyengar's question, isn't there also an argument for reintroducing some of these? I read a blog on chess.com that modern play at the top level was becoming less adventurous due to computers and top level players knowledge of openings and strategy.  

True only by ones' definition of "adventurous" or not. If "normal" chess is becoming too repetitive for the liking, then that is what chess variants are for  Don't like remembering 30 moves of opening theory? Play live 960 (Fischer Random). Don't like the dimensions of a chess board suited for two players? Play 4 player chess. Don't like how linear the objective of the game is via checkmate? Play variants like 3+ or King of the Hill where there are alternate ways to win. "Normal" chess is pretty entertaining to me, but why not dabble into some variants if it is fun?