With the global economy once again bracing for uncertainty, we look back to almost a century ago when the situation was decidedly grimmer. The decade of economic contraction, mass unemployment, and suffering that is referred to as the Great Depression started with the crash of the stock market in the United States of America in 1929. However, with the importance of the American market to the global economy, the effects of the crash soon spilled over to much of the rest of the world

Far away from New York City, in their offices on the Rue Du Rhône in Geneva, the management of Patek Philippe were also feeling the effects of this downturn acutely. Stock that had been shipped around the world, from the US to Brazil, with duties and taxes paid for by the brand, sat unsold. Patek Philippe had over-leveraged itself financially and several rounds of salary cuts and instances of melting down precious-metal cases to pay staff were not looking like they would be enough to sustain the 90-year-old business.

As is often the case in moments of existential crisis, this period saw a number of fundamental decisions that would prove to be crucial to Patek Philippe’s modernisation and survival. The first order of business had to be the infusion of fresh capital. The brand had a prospective buyer in its movement manufacturer LeCoultre but it favoured the offer made by its dial maker, Stern Frères, headed by brothers Charles Henri and Jean Stern. The Stern brothers, with their majority stake in the company, hired Jean Pfister, a man who had something the brand’s new owners did not: experience running a watch brand.

This infusion of capital, technology, and business acumen was only part of the shift needed at Patek Philippe. The world had changed around the brand and the timepieces it was known for – with thick, precious-metal cases and ornate decoration – were sitting on shelves uncomfortably in an era of austerity. It is in the midst of this wholesale rethinking of the brand that the Ref. 96 was born in 1932. While it was not known as such at the time, it would come to represent the archetype not just for a line that would come to be known as the Calatrava, but of understated dress watches in general.

The Calatrava is often used as a byword for time-only dress watches by the brand – but what is it? We spoke with experts to answer this question. We also looked for rare and unusual executions of a watch known for its simplicity of form that show just how versatile the design has been over its 90-year history.

The Calatrava was a significant novelty, even if not wholly out of left field. Conservatively sized, but entirely appropriate for the era, the solid-gold case measured 31mm across, and stood 9mm tall off the wrist. John Nagayama, a Japan-based watch dealer specialising in vintage Patek Philippe and specifically the Ref. 96, believes there are three design features that were central to its identity – a slim, round case; flat bezel; and simple, flat lugs originating from the case that curve down. At its simplest, its face wore faceted, applied gold indices and minute-marker dots, and faceted dauphine hands. At 6 o’clock was the subsidiary seconds register, with radial markings and a leaf-style gold hand. The crown was substantial and unsigned, in keeping with the running theme of understated functionality. Powering it, at least initially, was a manually wound LeCoultre ebauche, as had been standard practice for Patek Philippe for much of its history up until then.

The Ref. 96’s plain exterior belied not only craft and design foresight but also how crucial the watch was to be for Patek Philippe’s survival. The dial, for instance, employed a technique where the Patek Philippe marque and the markings of the subsidiary seconds register were first engraved onto the plate before being painted in black enamel, which was then treated to fire. The minute track, another seemingly simple design detail, was created by a method called perlé that involves each marker machined by diamond drill so they were all exactly even to the eye. The lugs, instead of being soldered on as was the practice of the day, were integrated more seamlessly into the three-part case design that comprised the bezel, case, and caseback. The tapering lugs curved down – another design innovation that aided wearability.

The Ref. 96 would also be a home for Patek Philippe’s first in-house calibre for a wristwatch: a 12-ligne movement named the 120 (calibre 12’”120). This was a result of Sterns’ view that the brand needed to upgrade its technical abilities to design and fabricate its own movements, and Pfister was charged with executing this vision. Pfister’s team commenced work on the 12’”120 that would replace the 12-ligne LeCoultre blank that was being used in the Ref. 96 prior to 1934. Interestingly, the blanks were repurposed from the Gondolo, a watch whose sales were hit particularly hard by the Great Depression.

Another way the Ref. 96 marked a break from Patek Philippe’s past was in its name. Before this, the brand logged watches simply by their case number, never using names either for watches or for the same design family. Born out of the rigour and efficiency the Sterns hoped to bring to the business, and perhaps inspired by the Rolex Oyster’s growing brand recall, the first numbered reference, the Ref. 96, was born. The Ref. 96 played a significant role in reviving Patek Philippe, and its successors would continue to be vehicles for the brand’s innovations. For instance, when Rolex’s 20-year patent on the first self-winding movement was up, Patek Philippe was able to bring its own version of the technology to market in the form of the calibre 12’”600 AT in 1953. It picked the Ref. 2526 to bring it to market. The watch, produced in precious metals, also featured the brand’s first water resistant case, thanks to a screw-back case.

The Ref. 96, produced between 1932 and 1973, was expressed through a wide variety of dial configurations, featuring no seconds, subsidiary seconds, and offset subsidiary seconds as well as centre seconds (thanks to a clever redesign of the 12’”120’s sub seconds incorporating an additional mechanism by Victorin Piguet that gave it its ‘indirect central seconds’ name). It has featured indices of all varieties – Arabic, Breguet, Roman, and precious stone – not to mention hands from dauphine and baton to pencil and leaf-style. Case material was yet another area for variety. John Reardon, Founder of Collectability says, “Style variations of the Ref. 96 changed over time based on logo changes over time, points of sale, and even local tastes – for starters, the long signature (PATEK PHILIPPE & Co) vs short signature (PATEK PHILIPPE). This transition occurred circa 1948. Then, of course, [there were] retailer signatures found in many different locations on the dial. Finally, local tastes dictated case and metal preferences.”

The Calatrava success was definitely fuelled in part by this diversity. Today the design language it established is seen as foundational to the line. This is despite the fact that the Ref. 96’s pre-dated the Calatrava name. “If you asked someone to see a Calatrava at a Patek [Philippe] store in 1945 or even 1965, for example, you would get a blank stare. The term 'Calatrava' is a mid 1980s marketing invention for a classic round Patek Philippe,” says Reardon.

While the brand had trademarked the Calatrava cross in 1887 and had been using the stylised Greek cross on casebacks, crowns and clasps since the 1960s, Patek Philippe had never used the name to refer to any particular line of watches until the 1980s. Despite this, it is a widely held belief within the community of dedicated collectors that the Ref. 96 laid the archetype for the Calatrava line of the future.

Reardon says, “For me, a Calatrava is the classic shape of a Ref. 96 from the 1930s to 1970s. That is about as Calatrava as it gets for me and then the endless list of classic round Pateks that the 96 inspired.” Nagayama echoes this sentiment.

The success of the Ref. 96 resulted in a family of references all closely linked to the design of the original. The Ref. 570 was released in 1938; although an upsized rendition featuring a case measuring 35.5mm across, it is an example most enthusiasts agree closely follows the original formula. The Ref. 2457’s dimensions make it an even more faithful descendant of the Ref. 96. Nagayama also points to others such as the diminutive 28mm Ref. 437 and 438, and others such as the Ref. 2508, 2509, 2545 (32mm), 2555 (31mm) and 3439 (32mm), as examples of typical Calatrava models. Reardon thinks others such as the 3796 and 3919 and more recent references like the 5196 also make the cut. Others wager that references such as the 5026, with its flat bezel and subsidiary seconds register, albeit offset, also fall within the historical parameters of a Calatrava.

Case size was one of the major areas of variation. Reardon points out that “one of the smallest classic Calatravas was the Ref. 1289 at 20 mm and one of the largest pre-modern era Calatravas was the Ref. 530, at a relatively massive 36.5mm”.

Then there are examples like the ref. 2526. While enthusiasts often point to its obvious visual similarities with the ref. 96, Reardon doesn’t agree. “I don't generally think of a 2526 as a Calatrava, but I guess it is with a loosely accepted definition.” he says.

The point of contention in the case of this reference is the shape and general appearance of the lugs on the 2526 – they are more rounded than the ref. 96’s. Nagayama says, “The ref. 2526 doesn’t have the flat bezel and the shape of lugs is completely different from [the ref.] 96 or 570. To me, [the] 2526 is not a Calatrava, but it’s obviously one of the most important references ever made by Patek Philippe.”

The differences in opinion when discussing the Calatrava are emblematic of a watch that didn’t start life as a cohesive line. This has resulted in enthusiasts often erroneously labelling any time-only watch with a classic design from Patek Philippe as a Calatrava. On the other end of the spectrum, some apply the strictest design criteria set by the ref. 96 to determine if a reference qualifies as a Calatrava.

The brand itself has taken a less prescriptive approach to the line over the years. The ref. 3520D is an example of this. Marked apart by its straight lugs and a hobnail guilloche bezel, it was some way removed from the ref. 96. However, since its launch in 1974, the reference established design cues that have stood the test of time. While references such as 3919, 3992, 5120, and 5119 are clearly related, design details like the ‘Clous de Paris’ bezel are still part of the modern Calatrava offering in the form of the ref. 6119.

Alongside the ref. 5227, the Calatrava line of today also includes references such as the 5226 as well as the ref. 7200. The last one takes cues from the Ref. 3960, an officer-style watch that was released on the brand’s 150th anniversary in 1989 as part of the Calatrava line that Patek Philippe had established by then. “Today Patek [Philippe] very loosely describes the Calatrava line as ‘legendary purity’ and basically lumps all round non-complicated Pateks in the category,” says Reardon. “At the very core of Patek Philippe time-only offerings, I expect we will always see a ‘Calatrava’. The definition has evolved over time [and will continue to do so] but the classic round dress watch will always be at the core of Patek Philippe's design vocabulary.”

To Nagayama, the Ref. 5196 is the last descendant of the Ref. 96, and the current production reference is a nod to that lineage.

We might never definitively settle the debate on the Calatrava, which is perhaps to be expected when the line traces its history back to a 90-year-old watch. It came at a crucial time for the brand that was in the midst of modernising itself to survive. While this resulted in obvious improvements such as a comprehensible nomenclature, the sheer variety of the Ref. 96 harks back to a time when watch brands were not restricted by the harsh guidelines of a watch line. This willingness to colour outside the lines gave us some interesting examples, some of which were made in small quantities, further adding to their desirability. This remained the case for much of the pre-modern references.

In the 1980s Patek Philippe at once officially drew a connection back to the Ref. 96 and also showed a willingness to diversify the line, further complicating efforts to clearly define what a Calatrava is. While we’re unlikely to see the kind of variety in terms of dial layout that the Calatrava was known for, this perhaps represents the kind of variety we can still enjoy in the era of modern watchmaking.