Ruy Lopez, Neo-Arkhangelsk Variation

In algebraic notation, b5 represents column b and row five. Under the definition used by this catalog, the Neo-Arkhangelsk arises within the Morphy Defense when Black advances b5, makes White’s bishop retreat to b3, and moves the f8-bishop to c5. The b5-pawn gains queenside space, on the side of the board where the queens began, while the bishop on c5 enters the game with pressure on f2 and the central squares.

Black chooses immediate activity instead of a slow closed setup. Black can prepare castling, the special move that moves the king and a rook, and seek counterplay, meaning active threats that prevent White from playing without opposition. White commonly challenges the b5-pawn with a4 or builds the center with c3 and d4. The pawn on b5 gives Black space, but it can also become a target if it lacks support.

Naming varies among sources. Lichess identifies the sequence with b5 followed by the bishop move to c5 as the Neo-Arkhangelsk, and that is the position shown here. Some databases call the immediate bishop move to c5, without inserting b5, the Neo-Arkhangelsk; other references call that line the Møller Defense. Always check the move sequence, not only the name.