The French Navy's design staff spent the decade following the 1922 Washington Naval Treaty attempting to produce a satisfactory design to fill 70,000 tons as allowed by the treaty.
Initially, the French sought a reply to the Italian Trento-class cruisers of 1925, but all proposals were rejected.
A 17,500-ton cruiser, which could have handled the Trentos, was inadequate against the old Italian battleships, however, and the 37,000-ton battlecruiser concepts were prohibitively expensive and would jeopardize further naval limitation talks.
These attempts were followed by an intermediate design for a 23,690-ton protected cruiser in 1929; it was armed with 305 mm (12 in) guns, armored against 203 mm (8 in) guns, and had a speed of 29 kn (54 km/h; 33 mph).
Visually, it bore a profile strikingly similar to the final Dunkerque.

The German Deutschland-class cruisers became the new focus for French naval architects in 1929.
The design had to respect the 1930 London Naval Treaty, which limited the French to two 23,333-ton ships until 1936.
Drawing upon previous work, the French developed a 23,333-ton design armed with 305 mm guns, armored against the German cruisers' 280 mm (11 in) guns, and with a speed of 30 knots (56 km/h; 35 mph).
As with the final Dunkerque, the main artillery was concentrated entirely forward.
The design was rejected by the French parliament in July 1931 and sent back for revision.
The final revision grew to 26,500 tons; the 305 mm guns were replaced by 330mm/50 Modèle 1931 guns, the armor was slightly improved, and the speed slightly decreased.
Parliamentary approval was granted in early 1932, and Dunkerque was ordered on 26 October.
The French Navy's design staff spent the decade following the 1922 Washington Naval Treaty attempting to produce a satisfactory design to fill 70,000 tons as allowed by the treaty. Initially, the French sought a reply to the Italian Trento-class cruisers of 1925, but all proposals were rejected. A 17,500-ton cruiser, which could have handled the Trentos, was inadequate against the old Italian battleships, however, and the 37,000-ton battlecruiser concepts were prohibitively expensive and would jeopardize further naval limitation talks. These attempts were followed by an intermediate design for a 23,690-ton protected cruiser in 1929; it was armed with 305 mm (12 in) guns, armored against 203 mm (8 in) guns, and had a speed of 29 kn (54 km/h; 33 mph). Visually, it bore a profile strikingly similar to the final Dunkerque.
The German Deutschland-class cruisers became the new focus for French naval architects in 1929. The design had to respect the 1930 London Naval Treaty, which limited the French to two 23,333-ton ships until 1936. Drawing upon previous work, the French developed a 23,333-ton design armed with 305 mm guns, armored against the German cruisers' 280 mm (11 in) guns, and with a speed of 30 knots (56 km/h; 35 mph). As with the final Dunkerque, the main artillery was concentrated entirely forward. The design was rejected by the French parliament in July 1931 and sent back for revision. The final revision grew to 26,500 tons; the 305 mm guns were replaced by 330mm/50 Modèle 1931 guns, the armor was slightly improved, and the speed slightly decreased. Parliamentary approval was granted in early 1932, and Dunkerque was ordered on 26 October.
French battleship Dunkerque