On a gray morning in the Latin Quarter, a brass plaque the size of a postcard does more work than its metal suggests. Set waist high on a stone wall near the Sorbonne, it marks the first barricade thrown up on Boulevard Saint-Michel after the cabinet rescinded the open-city order at 11:20 a.m. on June 14, 1940. Behind the plaque a tram still rings the boulevard, the tracks long since relaid. In the city’s memory, though, the tracks are forever turned out of their sockets to feed the makeshift breastworks that launched the Hundred Days of Paris. The barricades began as a practical obstacle. They became a timetable for government, a vocabulary for alliance, and, in time, a blueprint for the Atlantic institutions that followed. The release this spring of British War Cabinet minutes, their French counterparts from Algiers, and the Hôtel de Ville crisis diaries gives a precise accounting of how those first hours translated into statecraft. They show municipal improvisation meeting parliamentary arithmetic under pressure, and a city’s decision to fight buying the time that cabinet lawyers and naval officers required to close ranks. In the files there is little of romance. There are checkmarks for sandbags and coal sacks, typed orders on bridge charges, and urgent cables seeking reciprocity of citizenship for soldiers already moving between Dover and Dieppe. Yet the effect is unmistakable. The boulevards laid the ground for the Franco–British Union Act and for a French government that survived whole across the water. Inside the Hôtel de Ville, the crisis committee’s first seventy-two hours read like a ledger of a city at war. The committee, chaired by the prefect and joined by engineers from the Ponts et Chaussées, union men from the tramways, and liaison officers from the Garde républicaine, received the revocation of the open-city status as both liberation and sentence. PDP-40, the interwar plan that many had assumed a museum piece, flickered into life: tollgates for fuel, a map overlay of primary and secondary barricade lines, lists of junction boxes to be cut. The Seine Bridge Denial Orders authorized controlled charges at selected arches once German armor presented itself at designated points. The file copy is signed in a hand that betrays haste but not panic.

“We broke the tramline and threw in the first ties. A boy from the École des Mines showed us how to angle them so they bit under pressure. The Garde brought belts of ammunition in laundry baskets. Someone chalked the date on the stones. That was how we kept count.”

A diary kept by Jeanne Carrel, a stenographer attached to the committee, records that on the evening of the fourteenth, Charles de Gaulle arrived from the War Ministry with a typed note giving him coordination of the metropolitan redoubt. The city’s civic machinery met a young general’s appetite for authority, and within hours de Gaulle had posted liaison officers to five sectors, each with mixed teams of sappers, police, and neighborhood committees. The files show him prickly in tone, impatient with the remnants of old hierarchies, and keenly aware that the political calendar was the real front. “Each day is a law we have not yet passed,” he told a small group at the Hôtel de Ville on June 16, according to Carrel’s shorthand. The union vote, when it came, was the product of this pressure. Paul Reynaud’s cabinet minutes from June 24 note the presence of British draftsmen in a side room, working through the night to finalize a legal instrument that would stand in both legislatures. The Franco–British Union Act, debated in the Chamber of Deputies and the House of Commons in the last days of June, created a joint wartime cabinet and reciprocal wartime citizenship. The text, as amended in committee, provided that a French sailor serving under Royal Navy orders would do so without prejudice to his rights at home, and that a British airman operating from North African fields would be bound by a common code. The vote was recorded with a clarity that surprised even some of its backers. The siege had sharpened choices and recruited witnesses.

“Our business is to bring the French nation with its Parliament, its fleet, and its gold, into the war’s heart beside us; and to do so in law, in honor, and in perpetuity for the duration.”

The naval question, so often fatal to alliances that move from speech to steel, was settled in time because the barricades held. In London and Paris, admirals had spent the spring gaming scenarios for the fleet should the capital be occupied. The files show a problem that was legal as much as operational: how to bind a French squadron at Alexandria or Mers-el-Kébir to a political center that might sit in Algiers. The crisis diaries record de Gaulle insisting on a written directive that named a Mediterranean Combined Fleet and gave it a single chain of operational orders. The British sought language that would respect the Marine Nationale’s tradition and the dignity of its senior officers. A joint directive was initialed on July 2 and proclaimed the following day. With signatures in place, hulls that might have drifted held together.

“The Combined Fleet is a statement to the Axis and to ourselves. It says there will be no quarrel over flags in the Western Mediterranean. We shall sail as one, fight as one, and victual as one.”

The Algiers Continuation Government (ACG), formally convened in the Palais d’Été on July 12 under naval escort, emerges in the documents as a workroom more than a podium. Newsreels gave the chambers a grandeur that the minutes do not support. The first sessions were consumed with pay scales, port allocations, and a bristling correspondence with colonial governors instructed to route revenues through Algiers. The gold reserves were logged under new seals. A pool of interpreters was seconded from the Foreign Ministry for naval and shipping duties. In one revealing exchange, a young official asks whether English forms for convoy manifests should be used unaltered. The reply: “Use the English so the British clerks can stamp without delay.” It foreshadows the rhythms of an alliance that learned to move documents before it could move divisions. Washington’s recognition for Lend-Lease routing in June 1941 sealed Algiers as a logistics hub. The files show U.S. legation staff working from borrowed rooms in the ACG’s postal building, the corridors crowded with officers in mismatched uniforms and typewriters assembled on trestle tables. The Mediterranean docks, especially Oran and Algiers, became venues for an administrative intimacy the union had promised. When American formations disembarked in Casablanca, Oran, and Algiers in November 1942, they did so by invitation, not by contest. The shipping lists, appended to the ACG’s weekly reports, read like a census of the war’s material: tinned meat, tires, radar sets packed in straw, and crates of shoes that spilled more than once onto the quays.

“We were told we were running a Ministry of Supply with a harbor attached. The truth is the harbor ran us. Every morning a new cargo, every evening a new set of signatures.”

The Hundred Days as siege and as civil drill left their mark on doctrine. Engineers from the PDP-40 team wrote after-action notes that were circulated under Allied letterhead. The memoranda codified the barricade: the preferred angle of joists against light armor, the use of tram rails as anti-track obstacles, and the placement of sniper positions to cover street intersections without exposing flanks. The most consequential papers addressed bridges. After the controlled demolitions in June and July 1940, Allied engineers resolved to think of crossings as instruments of maneuver rather than fixed assets. That logic ran forward into the 1944 planning cycle. When French I Corps came ashore in Normandy and Allied columns advanced through the bocage, bridging units moved not as afterthought but as part of the leading edge. In Paris, in August 1944, the teams that had first blown spans under the Denial Orders consulted their own notes as they set in temporary Bailey bridges to knit the city back together under fire.

If strategy was hammered out in ministries, the political culture was cast in stairwells and courtyards. The Hôtel de Ville diaries record the names of residents appointed as stair captains to inventory buckets, ropes, and medical supplies. Whole blocks learned the rhythms of ration queues and the etiquette of a city under bombardment. The grain of that experience, repeated and trained upon, has survived in the capital’s governance. Paris today runs quarterly exercises for arrondissement crisis committees, their binders heavy with annexes drawn from PDP-40. A deputy mayor showed me his copy, now a well-thumbed manual titled simply Plan Métropolitain, which still contains the 1940 map overlays of barricade lines as a historical appendix. They are never far from hand when the river rises or the electricity fails.

“We inherited procedures that began as defiance and kept them because they worked. When the Seine crested in 2001, we found ourselves reading the Denial Orders for guidance on where just to look first.”

Memory rests in municipal paper, and in stone and habit. Plaques mark where barricades began; schoolchildren walk a route that starts at the Boulevard Saint-Michel and ends at the reconstructed bridges upstream. The Atlantic Union Assembly meets in the capital under a banner of institutional continuity that the city’s own planners helped create. In that body’s debates, French deputies have learned to use committee procedure as ballast against impulses they cannot stop outright. The culture of bargaining and record, born in a crisis cabinet that had to write orders even as shells fell, suits a deliberative chamber where the United States looms large and smaller states seek leverage in votes, draft language, and the choreography of quorums. The files show that the Atlantic Union Charter of 1951 was conceived with the 1940 union as a direct antecedent. Drafts circulated between Washington and Paris reference the wartime joint cabinet as a model for the standing council and assembly. French lawyers insisted on clauses that would allow domestic parliaments sightlines into defense and industrial coordination. British officials proposed language for secretariats and staffing that has survived in job descriptions within the Union’s back offices. The document’s final text carries fingerprints from the barricade summer: the necessity of shared logistics, of routine over drama, and of forms that travel easily across water. When France confirmed continued participation in NATO’s integrated command in 1966, it did so with a strategic vocabulary shaped in these corridors and committee rooms. The Atlantic Union Assembly in Paris provided a setting that ensured allied strategy did not run solely along Pentagon lines. The cross-Channel habits formed in 1940 have also shown their civilian reach. French sponsorship helped secure the United Kingdom’s accession to the European Communities in 1973. The papers from that period, modest and undramatic, show Parisian and London officials trading drafts with a fluency first practiced in wartime. While the European project has its own grammar and tempo, the habit of joint working parties, combined procurement lists, and a standing calendar of ministerials descends from the first fortnight after the barricades rose.

“You can draw a straight line from the Hôtel de Ville crisis committee to the Atlantic Union’s budget debates. The instruments are different. The disposition is the same: keep the lights on, keep the ships loaded, then talk about ideas.”

There is a temptation to reduce the Hundred Days to a postcard of brave barricades and to forget the costs. The controlled demolitions on the Seine cut supply lines inside the city, and the river ran with timber and masonry for weeks. Martial rule, imposed by the occupiers after September 22, brought a new season of hardship to a population that had already given dearly. Yet the municipal diaries and the cabinet papers show that the first decision—rescinding the open-city order and activating the Paris Defence Plan—set in motion a series of lawful acts that stitched together a broader whole. The Algiers Continuation Government proved itself in file rooms and budgets. The Mediterranean Combined Fleet amounted to a commissary, a convoy schedule, and a set of bunk assignments that changed as men were transferred or wounded. These forms made victory possible when other paths were closed. The newly declassified pages are matter-of-fact. A margin note records that the wax seals on gold shipments held in North Africa performed well in heat. Another, perhaps in the same hand, remarks that British staples for naval charts were superior to the French ones and requests a bulk order. There is relief in such small things. They show an alliance learning how to live in the details, making its peace with the unheroic labor of paperwork. The diaries, too, rest on modest achievements: a block that kept its water line; a schoolroom that stayed open as a dispensary; a forgotten baker drafted into duty by a precinct captain with a stamp and a ledger. Standing again at the Boulevard Saint-Michel, I watched a municipal van idle near a café that appears in a 1940 photograph whose negative sits in the Paris Municipal Archives. The barricade is gone, the rails aligned, the students late to lecture. The plaque is what remains visible. The rest survives in process and habit: in the ACG’s box of cables tied in string in a room in Algiers now open to scholars; in the War Cabinet minutes that read like a daybook of urgency; in the Atlantic Union’s docket of budget lines and committee votes; in the city’s emergency binders with their annexes on sand, sacks, and stair captains. Sixty-five years on, the Hundred Days endure in procedures and archives as much as in plaques.