Introduction: The Paradox of French Armor in World War II
When discussing the armored forces of the Second World War, popular history often gravitates toward the iconic German Tigers and Panthers, the rugged Soviet T-34s, or the relentless American M4 Shermans. Yet, an objective evaluation of pre-war and early-war military engineering reveals a fascinating historical paradox: in May 1940, the French Republic possessed arguably the most heavily armored and technologically advanced tank fleet in the world.
Far from being universally obsolete, French industry had produced remarkable machines designed to fight and win the next great European conflict. Among these, two primary contenders emerge when determining France's absolute best tank of the war: the cavalry's sleek SOMUA S35 medium tank and the infantry's formidable Char B1 bis heavy breakthrough tank.
The Contenders: Engineering Excellence Meets Doctrine
To understand France's premier armored vehicle, one must first dismantle the persistent myth that French tanks in 1940 were universally inferior or outdated. In terms of raw mechanical design, armor thickness, and firepower, French engineers were pioneers. However, their creations were constrained by the strict tactical doctrines dictated by French High Command, which categorized tanks rigidly based on whether they were meant to support slow infantry advances or conduct sweeping cavalry maneuvers.
1. The SOMUA S35: The Cavalry Masterpiece
Developed by the mechanical engineering firm SOMUA (a subsidiary of Schneider) starting in 1934, the Automitrailleuse de Combat modèle 1935 S (better known as the SOMUA S35) was designed for the Divisions Légères Mécaniques (DLM)—the mechanized cavalry units.
Armor Protection: The S35 was groundbreaking because it utilized a bolted-together cast-armor hull and turret.
With a maximum thickness of 47 mm on the hull front and turret, it was virtually immune to standard German anti-tank guns (such as the 3.7 cm Pak 36) at normal combat ranges. Mobility: Driven by a 190-horsepower V8 engine, the 17-ton vehicle could reach respectable speeds of up to 45 km/h on roads.
This gave it exceptional operational mobility, fitting the cavalry requirement for deep exploitation and flanking maneuvers. Firepower: Armed with a long-barreled SA 35 47 mm main gun and a coaxial 7.5 mm Reibel machine gun housed in an APX 1 CE turret, the S35 possessed a weapon capable of penetrating the armor of any German tank fielded in 1940 at standard combat ranges.
2. The Char B1 bis: The Impenetrable Fortress
While the S35 ruled the cavalry, the Char B1 bis was engineered as a specialized infantry support and breakthrough weapon.
Dual-Weapon System: The Char B1 bis featured a unique dual-armament setup. It mounted a low-velocity 75 mm SA 35 hull-mounted howitzer intended for destroying fortifications and pillboxes, alongside a high-velocity 47 mm SA 34 (later SA 35) gun in a cast turret intended for anti-tank duties.
Unprecedented Armor: With up to 60 mm of frontal and side armor, the Char B1 bis was a literal rolling fortress.
During the fighting in May 1940, individual B1 bis tanks—most famously Eure, commanded by Captain Pierre Bilotte—absorbed dozens of direct hits from German anti-tank weapons without suffering a single penetration, while systematically destroying multiple German Panzer III and IV tanks in return.
Comparative Analysis: Strengths and Critical Flaws
Despite their incredible specifications on paper, both tanks suffered from design quirks and institutional oversights that hindered their overall effectiveness in combat.
The primary Achilles' heel for both vehicles was not their mechanical reliability or armor profiles, but their ergonomic and operational design choices.
For instance, the SOMUA S35 suffered from a severely overburdened one-man turret.
Similarly, the Char B1 bis required its driver to also aim the heavy 75 mm hull gun by shifting the entire vehicle using a complex mechanism called the Naëder steering system, adding immense workload to the crew inside a cramped combat compartment.
This video provides an excellent visual and interior breakdown of the Char B1, highlighting its unique physical layout, dual-weapon configuration, and complex internal mechanics.
Strategic and Tactical Doctrine: The Battle of France
The true test of any military vehicle lies not on the testing grounds, but in the crucible of war. When the German Blitzkrieg struck Western Europe in May 1940, French armor designs faced an adversary that capitalized heavily on combined arms and radio-equipped command structures.
Infantry Support vs. Cavalry Exploitation: French doctrine strictly bifurcated tank deployment. Infantry tanks like the Char B1 bis were designed to crawl alongside foot soldiers, methodically cracking heavily fortified enemy strongpoints. Meanwhile, medium cavalry options like the SOMUA S35 were engineered for deep independent breakthroughs, exploiting gaps to disrupt rear lines.
The Communication Handicap: Despite possessing superior individual protection and firepower compared to early German Panzer III and Panzer IV tanks, French tactical mobility was severely hampered.
Many combat vehicles lacked functional two-way radios, forcing units to rely on primitive visual flag signals or courier motorcycles.
Comparative Analysis: The Contenders
Evaluating France's finest armored asset requires balancing raw specifications against operational realities. Two primary candidates dominate this historical discussion:
While the Char B1 bis was arguably the most terrifying individual tank on any European battlefield in 1940—capable of shrugging off virtually all German anti-tank rounds while obliterating opposing armor—its extreme mechanical complexity, high fuel consumption, and single-man turret placed immense stress on its crew.
The Verdict: Crown of French Armor
Ultimately, the SOMUA S35 edges out as the best all-around tank produced by France during this era. Its advanced cast-armor hull design provided exceptional ballistic protection, while its 47mm main gun could easily penetrate contemporary German armor at standard combat ranges.
"The SOMUA S35 combined mobility, thick skin, and a high-velocity weapon system that represented the absolute pinnacle of pre-war European medium tank design."
However, brilliant engineering could not compensate for flawed strategic deployment. Confined to piecemeal counterattacks and crippled by rigid command structures, these magnificent machines were largely prevented from demonstrating their full potential.
Legacy and Post-War Recovery
The story of French wartime engineering did not entirely conclude with the tragedy of 1940. As Allied forces liberated French territory, surviving remnants of these vehicles—alongside examples retrieved from German hands—were occasionally patched back together by local resistance units and regular troops.
This video provides an in-depth breakdown of the various armored vehicles fielded by France during the conflict, offering additional context on how the S35 and Char B1 bis compared to their contemporaries.