The London System takes its name from its association with the strong London tournament of 1922. The underlying idea of developing a bishop to f4 was older; the event helped attach a memorable name to the setup. More recent advocates, including Gata Kamsky and Magnus Carlsen, have shown that its apparently modest development can support serious positional and attacking play.
Its defining feature is the early dark-squared bishop development. White usually plays d4 and Bf4 before building a supporting centre with e3 and often c3. That order matters: playing e3 first can leave the bishop behind its own pawns. The diagram isolates the decision, making the opening easier to remember as a piece-development idea rather than a fixed sequence.
Calling it a system describes recurring arrangements, not permission to ignore Black. Against pressure from ...c5 or ...Qb6, White may need to defend d4 or b2 before completing the usual setup. Against a kingside fianchetto, the bishop placements and central plans can change. Those branches are part of learning the London properly.
Use the history as a memory anchor, then test the position. Practise the main line and explain the role of Bf4, e3 and c3. After that, add one active Black response. The useful inheritance from the opening's development is a flexible structure with recognisable plans, rather than a promise that the same moves work against everything.
Try this at the board
Before playing e3, locate the dark-squared bishop and explain why its position matters.