Comments/Ratings for a Single Item

I always enjoy hearing about variants for three or more players--
especially if the rules and layout are well-conceived. This looks like a
variant I'd be interested in playing, but it looks like I'll have to
construct my own board. If you're playing with people who are on the same
level as you, 4-player chess can be quite exciting.

However, I find it's most interesting when you play free-for-all, and
pieces of a checkmated king are taken control of by the opponent who mated
him. In that case, it's fun to see the remaining two drop everything to
team up on the overpowered opponent, and then(if they survive) continue
decimating each other.

I remember one such game where a friend of mine had broken one such
'treaty', mating me while under the pretense that we were teaming up on
the other person. That little sidequest, however, cost him valuable time--
and later, the game.

Sorry, just a little reminiscing... keep up the good work!

Please, look at the German site 

http://www.Festungs-Schach.de

Sorry, I didn`t translate it into English.

Russian Fortress has four by fours (4x4) like Gala:
http://www.chessvariants.org/historic.dir/gala.html.
Recall that Flowerman recently has four by sixes (4x6):
http://www.chessvariants.org/index/displaycomment.php?commentid=24998.
Sub-boards are another great avenue toward proliferation. Reasonable sub-boards might vary from 1x1 to 7x7 for (49-7), 42 possibilities. Or even be odd-shaped like Ramayana:
http://www.chessvariants.org/large.dir/contest84/ramayanachess.html.

According to other comments here, and some of my own ideas, we can write about other kind of subvariants.

It is not mentioned what happen in case of attacking partner's pieces. Here is some possibilities of subvariants to deal with it

1. Attacking partner's pieces is not possible.
2. It is allowed to capture partner's pieces (other than a king), but you are not in check if being threatened only by a partner's pieces.
3. It is allowed to capture partner's pieces (including a king), and there is no check/mate (and therefore you can castle into/out of/through check); you need to capture the king.

One kind of subvariants can be the teams:

1. Partners across from each other.
2. Partners next to each other.
3. No teams.
4. Washizu-style: Partners next to each other, with one player of each team designated as "leader" and one as "supporter". The "supporter" plays immediately after the "leader". Your team instantly wins if the opposing leader's king is captured (or checkmated, depending on subvariant).

And there is winning conditions:

1. Russian: If you are checkmated, all of your pieces (including a king) is removed from the board and you take no more turns. Any team out of players loses.
2. West-European: You pass if you have no legal moves (for kick-the-king variant, also if you have no king). Checkmating both opponents simultaneously wins.
3. My rule: If you have no legal moves or if your king is captured, you pass your turn. If both players of a team pass without either making a move in between, that team loses the game.
4. Bradley's rule: Whenever a player is checkmated (or loses his king in kick-the-king), all of that player's pieces are changed to the color of whoever checkmated/captured him.

Lastly, there are subvariants dealing with fortress:

1. Normal: Each player deploys his three additional pieces inside the fortress at his own choice and it is then visible to everyone.
2. Hidden version: Variant of the above where you cannot see opponent's pieces in opponent's fortresses (you can see them in your/your partner's fortresses, or when they are in the main board, and you can still see your and your team's pieces in any fortress).
3. Random hidden version: Further variant where in addition to hiding pieces like that, the pieces are deployed at random in valid positions (individually for each player).

Please check my 2015 paper on this game in Board Game Studies Journal 9, pp. 41-49: http://bgsj.ludus-opuscula.org/PDF_Files/41_49_Markov_web.pdf

As for "Tchigorin, Capablanca and Lenin": photos of Ulyanov's chess table on the internet show a board with 160 squares, i.e. the western variant with 3 additional rows, and no fortresses. Information on Capablanca, I suspect, is due to mixing up double chess (which Capablanca did play indeed), and four-handed chess. No idea about Tchigorin but I doubt it.

Four stars for the original chessboard.

This game was very popular almost two centuries ago and lots of famous people used to play it.