it's way too easy to get hung up on one Path to Enlightenment. Unfortunately, you are as likely to find Enlightenment in a drop of water as in the choice of a handgun.

There are though, certain guns that when they appeared, everything changed. These handguns were blazing milestones along the way. And most are still very competitive with all of the new ones that come along. That alone says that here is something new, something that is a primary condition. Each of these guns added something very significant that No handgun since then could Not include as a basic design feature.

I'm sure we can all put together a list of what we consider to be those most important handguns. Here is mine and I'll be interested in seeing what you folk consider the truly significant handguns.

I'm going to start with the Colt Single Action Army. There were others that were very similar, and even some that might have been better. But the Colt SAA simply changed the whole landscape. Here was a handgun that required only one component. No caps, powder, charges, ball. It was easy to load and reload. It was balanced and accurate and could be carried loaded for days or weeks on end.

My second choice was the S&W First Model American. Here was the first handgun that we'd recognize as being modern. It was a top break design and beloved by the Calvary. When you broke it open you could load all six chambers while riding a charging horse in the heat of battle. At that moment the SAA became as worthless as yesterdays newspaper.

When Smith & Wesson introduced the Hand Ejector, the first model with a swing out cylinder that all revolvers today use, there was another significant milestone. but unlike the effect of the advent of the First Model, the Hand ejector did not obsolete the Top Break models. S&W continued making top break models right up to WWII. Others such as Harrington & Richardson continued top break models right up to very recently.

The Colt 1911 was another milestone. It wasn't the first semi-automatic, they had been around for many decades, but it was the first that had been able to stand up to a rigorous Army testing. as with the Hand Ejector, the 1911 didn't mean that revolvers would go away, but it did legitimize semi-automatic pistols as something that must be taken seriously.

The advantage that a magazine offered for the average combat soldier was quickly recognized world wide, and just about every Military began a search for a semi-automatic for their soldiers. There were many really great attempts, notably the Luger. But none of those really worked when in the field. the Luger had so many moving parts and such a complex works that they couldn't be counted of except on parade and at matches.

But two others did work in the field. The P-35, another Browning design was  the first successful hicap semi-automatic to come along. It met all the requirement of a field weapon, was reliable, cheap to mass-produce and held twice as many rounds as the 1911. Even with all of that capacity it was still a slim and light pistol.

The other real milestone was the Walther P-38. Here was a rugged semi-automatic that could be carried hammer down and fired double action first shot just like a revolver. In addition, it was just plain beautiful.

So those are my choices for the most significant handguns of the modern era. The Colt SAA, S&W First Model American, S&W Hand Ejector, Colt 1911, FN P-35 HiPower and the Walther P-38.

What would you list as the most significant handguns?

Interesting topic.  

I would agree with each firearm mentioned and only add one at the moment and that would be the Walther PP and PPK family of small DA autoloaders.   Pre-dating the P-38 and contributing to the DA and hammer lowering safety features of the P-38, they were some of the first concealment firearms that increased the safety of hammer down, loaded chamber carry.  Not striker fired like many of their contemporaries, such as the Brownings and Colts of the time.  

>>The Colt 1911 was another milestone. It wasn't the first semi-automatic, they had been around for many decades, but it was the first that had been able to stand up to a rigorous Army testing.<<
Got to disagree.  First, it was less than 20 years between the development of the first working semi-automatic pistol and the 1911.  Second, in spite of your next paragraph, the Luger had passed the rigorous testing procedure and been adopted by the German Army before the 1911 was adopted by the U.S.  It had also passed military testing for acceptance in the German Navy and the Swiss military.
>>the Luger had so many moving parts and such a complex works that they couldn't be counted of except on parade and at matches.<<
I'm not sure where you got that bit of information, but it is in error.  The Luger reliability was considered very high at the Army Ordnance testing, and it proved to be a reliable handgun in two World Wars.  The Luger reputation for malfunctions came about later when shooters tried to feed it underpowered 9mm ammo post-WW2, and from the large number of poorly assembled "parts guns" tossed together late in the war. But a good quality Luger, fed the ammo it was designed for, the Luger is as reliable as anything else built at that time.
As for the P-38, I must say Beachboy has it right.  There was nothing new or innovative about the P-38, all the work for it had been done earlier with the  PP-series.
Finally, regarding your claim that the SAA "became as worthless as yesterdays newspaper" with the advent of the S&W, again it just isn't so.  The SAA was a sturdier design, and the S&W never really caught on with the cavalry, always playing a distant second to the SAA.

The P-38 differed from the PP in that the recoil springs were in the frame...neat idea and it did not share the same fixed barrel, having the locking block. I see few similarities with both, and wouldn't consider the PP a prototype for the P-38. In that context, it was the first service sized SA/DA.
OK, the US tested the P-08 and it did well, but wasn't it was already determined it had to be in .45 ACP?
The 1911 design stood the test of time, look how many makers there are to this day.
Anyway, generally agreeing with sigs list, (historical accuracy notwithstanding) what handguns stood out to you, darm, beachboy, through the years?

Hmmmmm, very similar list for me.  
The Colt SAA for the way it feels in the hand.  The Remington c&b and later cartridge revolvers for the top strap/enclosed cylinder windows (Army/New Model Army/1875/1890, etc).  
The Merwin,Hubert's for their innovative touches (folding pocket hammers, large bore, small grip frame short barrels....concealment models)and unique ejection method.  
The Luger (handled a beautiful 1906 Swiss .30 yesterday, one of the one marked for Amercrobie and Fitch on the barrel), again more for the way it points and balances in the hand.  
Of course the JMB designs, to include the Colts 1903 and 1911 and the BHP/P35.
The Walther's as mentioned.
The H&K HK-4, P9 and VP-70 for their plastic frames.
I'll stop there.

I'm sure we can all put together a list of what we consider to be those most important handguns. Here is mine and I'll be interested in seeing what you folk consider the truly significant handguns.

As I said, Those are the ones that I consider as being the most significant and for the reasons stated.

What I'm interested in is to see What you good folk consider to be the most significant handguns.

>>The P-38 differed from the PP in that the recoil springs were in the frame...neat idea and it did not share the same fixed barrel, having the locking block.<<
No disagreement, but the justification that was given for selecting it was: "Here was a rugged semi-automatic that could be carried hammer down and fired double action first shot just like a revolver."  In that, it didn't break any new ground or provide anything innovative.
>>OK, the US tested the P-08 and it did well, but wasn't it was already determined it had to be in .45 ACP?<<
I'm not sure what that has to do with anything.  The statement dealt with the guns reliability, not with caliber.
>>what handguns stood out to you, darm, beachboy, through the years? <<
I'd pick the Colt Navy over the SAA.  It essentially gave us everything we were going to get later in the SAA except the enclosed cartridge.
The Walther PP-series double action autos.  The first design that showed the DA autoloader was a feasible firearm.
The S&W Model 60.  Few remember it now, but developing a stainless steel handgun was an earthshaking event at the time.
The Glock 17.  While polymer pistols had been around before, it was the Glock design that changed the way the world looks at handgun manufacturing.

Model 60...yup, I still favor stainless and the little Chief led the way. (nevermind the AMT hardballer with its two kinds of grease).
Let's pick apart the Glock...first it was shunned, now it is imitated.
Not so much because it was good or not, but being cheap and easy to manufacture.
Less hand fitting and minimal machining do increase profit margins and everybody wants in on that.
Ever wonder what the actual cost is to produce a Glock?
Agreed, the G-17 led to the acceptance of the molded gun. And is still taking off.