diff --git a/spec/lx_chess/game_spec.cr b/spec/lx_chess/game_spec.cr
index 5368e7d..1516358 100644
--- a/spec/lx_chess/game_spec.cr
+++ b/spec/lx_chess/game_spec.cr
@@ -4,11 +4,27 @@ require "../../src/lx_chess/piece"
 require "../../src/lx_chess/move_set"
 require "../../src/lx_chess/game"
 require "../../src/lx_chess/term_board"
+require "../../src/lx_chess/player"
+
+include LxChess
+
+describe Game do
+  describe "#castling=" do
+    it "sets the castling from a string" do
+      player_white = Player.new
+      player_black = Player.new
+      game = Game.new(players: [player_white, player_black])
+      game.castling = "kQ"
+      player_white.castle_king.should be_true
+      player_white.castle_queen.should be_false
+      player_black.castle_king.should be_false
+      player_black.castle_queen.should be_true
+    end
+  end
 
-describe LxChess::Game do
   describe "#find_king" do
     it "finds the black king" do
-      game = LxChess::Game.new
+      game = Game.new
       place(game.board, { "e1" => 'K', "e8" => 'k' })
       black_king = game.find_king(1)
       black_king.should_not be(nil)
@@ -16,7 +32,7 @@ describe LxChess::Game do
     end
 
     it "finds the white king" do
-      game = LxChess::Game.new
+      game = Game.new
       place(game.board, { "e1" => 'K', "e8" => 'k' })
       white_king = game.find_king(0)
       white_king.should_not be(nil)
@@ -26,8 +42,8 @@ describe LxChess::Game do
 
   describe "#moves" do
     it "correctly generates white pawn moves from the initial rank" do
-      game = LxChess::Game.new
-      game.board["e2"] = LxChess::Piece.from_fen('P')
+      game = Game.new
+      game.board["e2"] = Piece.from_fen('P')
       if move_set = game.moves("e2")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e3 e4])
@@ -37,8 +53,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates black pawn moves from the initial rank" do
-      game = LxChess::Game.new
-      game.board["e7"] = LxChess::Piece.from_fen('p')
+      game = Game.new
+      game.board["e7"] = Piece.from_fen('p')
       if move_set = game.moves("e7")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e6 e5])
@@ -48,8 +64,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates single white pawn moves" do
-      game = LxChess::Game.new
-      game.board["e3"] = LxChess::Piece.from_fen('P')
+      game = Game.new
+      game.board["e3"] = Piece.from_fen('P')
       if move_set = game.moves("e3")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e4])
@@ -59,8 +75,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates black pawn moves" do
-      game = LxChess::Game.new
-      game.board["e6"] = LxChess::Piece.from_fen('p')
+      game = Game.new
+      game.board["e6"] = Piece.from_fen('p')
       if move_set = game.moves("e6")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e5])
@@ -70,10 +86,10 @@ describe LxChess::Game do
     end
 
     it "generates captures for white pawns" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('P')
-      game.board["f5"] = LxChess::Piece.from_fen('p')
-      game.board["d5"] = LxChess::Piece.from_fen('p')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('P')
+      game.board["f5"] = Piece.from_fen('p')
+      game.board["d5"] = Piece.from_fen('p')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e5 d5 f5])
@@ -83,10 +99,10 @@ describe LxChess::Game do
     end
 
     it "does not generates captures pawns capturing own pieces" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('P')
-      game.board["f5"] = LxChess::Piece.from_fen('P')
-      game.board["d5"] = LxChess::Piece.from_fen('P')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('P')
+      game.board["f5"] = Piece.from_fen('P')
+      game.board["d5"] = Piece.from_fen('P')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[e5])
@@ -96,9 +112,9 @@ describe LxChess::Game do
     end
 
     it "generates captures for en passant targets" do
-      game = LxChess::Game.new
-      game.board["e5"] = LxChess::Piece.from_fen('P')
-      game.board["d5"] = LxChess::Piece.from_fen('p')
+      game = Game.new
+      game.board["e5"] = Piece.from_fen('P')
+      game.board["d5"] = Piece.from_fen('p')
       game.en_passant_target = "d6"
       if move_set = game.moves("e5")
         debug_board(game, move_set.moves)
@@ -109,8 +125,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates knight moves" do
-      game = LxChess::Game.new
-      game.board["c3"] = LxChess::Piece.from_fen('N')
+      game = Game.new
+      game.board["c3"] = Piece.from_fen('N')
       if move_set = game.moves("c3")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[a4 b5 d5 e4 e2 d1 b1 a2])
@@ -120,8 +136,8 @@ describe LxChess::Game do
     end
 
     it "does not generate knight moves that cross the left border edge" do
-      game = LxChess::Game.new
-      game.board["a1"] = LxChess::Piece.from_fen('N')
+      game = Game.new
+      game.board["a1"] = Piece.from_fen('N')
       if move_set = game.moves("a1")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[b3 c2])
@@ -131,8 +147,8 @@ describe LxChess::Game do
     end
 
     it "does not generate knight moves that cross the right border edge" do
-      game = LxChess::Game.new
-      game.board["h1"] = LxChess::Piece.from_fen('N')
+      game = Game.new
+      game.board["h1"] = Piece.from_fen('N')
       if move_set = game.moves("h1")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[f2 g3])
@@ -142,8 +158,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates rook moves" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('R')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('R')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -158,8 +174,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates bishop moves" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('B')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('B')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -174,8 +190,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates king moves" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('K')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('K')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -187,8 +203,8 @@ describe LxChess::Game do
     end
 
     it "does not generate king moves crossing the right border" do
-      game = LxChess::Game.new
-      game.board["h4"] = LxChess::Piece.from_fen('K')
+      game = Game.new
+      game.board["h4"] = Piece.from_fen('K')
       if move_set = game.moves("h4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -200,8 +216,8 @@ describe LxChess::Game do
     end
 
     it "correctly generates queen moves" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('Q')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('Q')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -220,9 +236,9 @@ describe LxChess::Game do
     end
 
     it "blocks moves when a piece is in the way" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('B')
-      game.board["f5"] = LxChess::Piece.from_fen('P')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('B')
+      game.board["f5"] = Piece.from_fen('P')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
@@ -236,9 +252,9 @@ describe LxChess::Game do
     end
 
     it "adds captures before blocking further moves" do
-      game = LxChess::Game.new
-      game.board["e4"] = LxChess::Piece.from_fen('B')
-      game.board["f5"] = LxChess::Piece.from_fen('p')
+      game = Game.new
+      game.board["e4"] = Piece.from_fen('B')
+      game.board["f5"] = Piece.from_fen('p')
       if move_set = game.moves("e4")
         debug_board(game, move_set.moves)
         move_set.moves.map { |m| game.board.cord(m) }.should eq(%w[
diff --git a/src/lx_chess.cr b/src/lx_chess.cr
index 0a7e0c3..bcc29b6 100644
--- a/src/lx_chess.cr
+++ b/src/lx_chess.cr
@@ -40,9 +40,13 @@ end
 
 log = [] of String
 fen = LxChess::Fen.parse(options["fen_string"]? || "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1")
+
 player_white = LxChess::Player.new
 player_black = LxChess::Player.new
+
 game = LxChess::Game.new(board: fen.board, players: [player_white, player_black])
+game.set_fen_attributes(fen)
+
 gb = LxChess::TermBoard.new(game.board)
 
 if theme = options["theme"]?
diff --git a/src/lx_chess/fen.cr b/src/lx_chess/fen.cr
index 87a99d4..0bf8ce3 100644
--- a/src/lx_chess/fen.cr
+++ b/src/lx_chess/fen.cr
@@ -1,6 +1,7 @@
 require "./board"
 require "./piece"
 require "./error"
+require "./player"
 
 module LxChess
   # Forsyth-Edwards Notation parser and converter
diff --git a/src/lx_chess/game.cr b/src/lx_chess/game.cr
index 371314e..5c43662 100644
--- a/src/lx_chess/game.cr
+++ b/src/lx_chess/game.cr
@@ -4,6 +4,7 @@ require "./notation"
 require "./move_set"
 require "./error"
 require "./pgn"
+require "./fen"
 
 module LxChess
   # Represents a standard game of Chess
@@ -32,6 +33,33 @@ module LxChess
       c_stirng.size == 0 ? "-" : c_stirng
     end
 
+    def castling=(string : String)
+      chars = string.chars
+      return false unless @players.size == 2
+      player_white, player_black = @players
+      player_white.castle_king = chars.includes?('k')
+      player_white.castle_queen = chars.includes?('q')
+      player_black.castle_king = chars.includes?('K')
+      player_black.castle_queen = chars.includes?('Q')
+    end
+
+    def set_fen_attributes(fen : Fen)
+      @turn = (fen.turn == "w" ? 0 : 1).to_i8
+      castling = fen.castling
+      en_passant_target = fen.en_passant
+      @fifty_move_rule = fen.halfmove_clock
+      @move_clock = fen.fullmove_counter * 2
+      @move_clock += 1 if fen.turn == "b"
+    end
+
+    def en_passant_target=(cord : String)
+      if cord =~ /[a-z]+\d+/
+        @en_passant_target = @board.index(cord)
+      else
+        @en_passant_target = nil
+      end
+    end
+
     def current_player
       @players[@turn]
     end