So I just wanted to make a quick educational blog about the periods of DC Comics history. If you already know some, a lot of this may be old info but I just wanted to make this assuming the reader knows basically nothing about DC history. If you want to make a division on characters feats based on time periods, this should help as it tells about the major time periods in DC Comics both from an in-universe major continuity change perspective and from a in-universe major events pespective. I hope this helps.
Golden Age: 1938?-1951?
So the Golden Age of Comics has a much blurrier start and end point than the other arcs. The Golden Age is notable in that its noticably less childish and goofy than its predecessor the Silver Age. Before the original Comics Code, characters tended to be rougher around the edge and less fixiated on being moral icons and the power range tended to be much more subdued as they focused more on criminals, scientists and dictators rather than metahuman enemies.
Pre-War Golden Age: 1938?-1941
The Golden Age didn't really have in-universe events the way that even the Silver Age would. By FAR the biggest event up to the end of the Golden Age was out of universe the United State joining World War 2. This notably changed the events in the story, causing a change from criminals and mad scientists as enemies to war stories. The first period usually agreed to start with Superman's introduction in 1938 and probably goes to 1941, the US entering the war. Technically there are some comics treated as canon to DC Comics that date even earlier including the stories of Slam Bradley and Dr. Occult.
War Period Golden Age: 1941-1945
The period in which DC produced comics while the second world war was going on and the comics had a greater focus on war stories and international enemies. Many specifically Patriotic themed heroes and teams were formed.
Post-War Period Golden Age: 1946-1951?
After the war, superhero comics began to slowly diminish. Heroes fought the red menace, or went back to fighting criminals, but it lacked the luster of fighting the nazis. Superhero comics were continually published making it unclear when the Golden Age actually "ended", with some arguing that it didn't end up until the VERY beginning of the Silver Age. Personally I put the end at the last appearence of the Golden Age Flash as star of his own book in 1951.
Interregnum/Atomic Age: 1951-1956
The Interregnum is the period between the Golden and Silver Age of comics when almost all comic series were canceled. The only characters to be continually published through the period, and indeed have been continually published since their first publishing were Superman, Batman, and Wonder Woman. This age is also called the Atomic Age due to the focus on atomic power and nuclear weapons in the storylines. This is when the power level of comics began to really ramp up.
The Comics Code created in 1954 to stifle any "corrupting" element of comics on the youths also hurt superhero comics dramatically, although ironically may be responsible for their rise to prominence again as while Superheroes were able to adapt to the Comics Code, Horror and Crime Comics which were at the time the dominant force in the comics industry found it nigh impossible to adapt to the draconic rules.
Silver Age of Comics: 1956-1971
Early Silver Age of Comics: 1956-1961
To adapt to the Comics Code strict terms, superheroes had to adapt to be uncontroversial, and adapted into a far more science-fiction feel. In 1956, the Flash was revamped with the more science-fiction Barry Allen. This was met with success and led to several others Heroes were revamped in the same sort of bright shiny idealistic scientific form. Completely kid-friendly and marketable, superhero comics began to return to prominence. In 1960 the heroes of this new age formed the Justice League of America, cementing this new universe as a cohesive "new" universe.
Middle Silver Age of Comics: 1961-1966
In 1961 Barry Allen crossed over with the Golden Age Flash Jay Garrick, establishing themselves as two seperate universes, beginning a host of multiversal adventures for the DC Earth including an annual teamup tradition between the JLA and their Golden Age counterpart the JSA. At the same time as multiple universes were being discovered in-universe, multiple universes being discovered out of universe, with the revival of Timely Comics as Marvel Comics, DC's chief competitor which would spur each other competitively.
By this points superheroes had grown to their definite height, even compared to the war period of the Golden Age.
Late Silver Age of Comics: 1966-1971
It's a bit vague, but overtime superhero comics began to become a bit more deliberately campier leaning more into the stereotypes of superhero comics. The Adam West Batman show begins airing in 66 and the Batman comics are deliberately written to match the style. Mystical elements were also slowely allowed to leak back into comics late into the Middle Silver Age with Zatanna's introduction in 1964, and the Spectre being reintroduced in 1966. In 1969 the Satelite era of the JLA named for their Watchtower Satelite Base they established above the Earth and known for character drama began and in 1970 comics legend Jack Kirby left Marvel to write for DC. Both in their own way were signaling the arrival of the next age.
Bronze Age of Comics: 1971-1986
With the waning of the Comics Code, comics quickly began to delve in newly allowed subject matter. Dark/Mature material, sexuality, moral ambiguity, politics, and religion all became common in superhero comics.
Early Bronze Age: 1971-1976
Beginning in DC Comics with the "Snowbirds don't fly" arc, an arc where Green Arrow finds out that his sidekick has been secretly using drugs, and Green Arrow and Green Lantern begin to tackle major social issues, this age is characterized by a maturing of the themes in the stories. This was also the year Jack Kirby started writing the New Gods which would be a central pillar to DC Cosmology.
In Marvel this was also the year that Green Goblin infamously caused the death of Spiderman's Girlfriend Gwen Stacy.
DC Explosion-Implosion: 1976-1980
During the mid 70s, Marvel had overtaken DC Comics in sales partialy due to producing signifigantly more comics. DC in an attempt to copy the formula produced signifignatly more comics, at signifigantly longer length, with higher prices. This decision was reversed later due to multiple factors, including blizzards two years straight, making comic production a less profitable venture overall leading to DC needing to cut down on production; events called the "DC Explosion" and the "DC Implosion" respectively.
While this may seem purely meta, on a practical level the canceled titles were not neccesarily the same as the ones started by the explosion, leading to a number of old titles coming to a sudden end and a number of new series beginning. Also as a fun note "Superman vs. The Amazing Spider-Man", the first inter-company crossover between DC and Marvel were released in 1976.
Late Bronze Series: 1981-1986
In retrospect, a lot of the events of the late Bronze Age seem to be specifically pointing towards the upcoming Dark Age. Miniseries became more popular, with series being made for a specific number of issues rather than made to go on indefinitely. Some writers. particularly writing on alternate Earths. wrote dark heavily political or adult stories such as V for Vendetta, a story about anarchism and fascism or Miracleman a defacto deconstruction of Superman, or the Marvel series Squadron Supreme about Superhero forcibly trying to make the Utopia in a superpowered coup. At the tail end of this period came "Whatever Happened to the Man of Tomorrow", a loving goodbye to the goofy idealistic Silver Age Superman from a world that left him behind.
Post-Crisis: 1986-2011
Crisis on Infinite Earths, likely the most influential event in comics occurs, an event that completely changes DC continuity, which features a cosmic battle against the Anti-Monitor where infinite worlds and lives are destroyed in the metafictional quest to simplify the convoluted and contradictory DC timeline.
Characters in the Post-Crisis period were initially vastly weaker than their Pre-Crisis counterparts, for the most part as part of the Crisis' purpose was to tone down the wacky power levels established in the Silver Age. Some characters would get stronger than they used too, some wouldn't, depending on the character.
1986-1994: The Dark Age of Comics
Superhero comics reach their darkest point. 1986 was the year the Crisis happened. It was the year Watchmen was released, a dark deconstruction of the superhero genre that continues to influence it to the present. 1986 was in-universe the year the Great Evil Beast first appeared and Swamp Thing tells it that its presence is a necessity.
This period was the period Superman perished in battle against the monster Doomsday, an event that made national news. This was when Batman got his back broken by Bane leading to him being temporarily replaced by Azrael, a far more violent and murderous personality, leading to mass erosion of Batman's reputation with the police, public, and superhero community. It was a period of darkness but a period of great artistry, the aforementioned Watchmen as well as the Sandman both being produced in this period.
This period ended with Zero Hour. After Green Lantern Hal Jordan's home city is completely destroyed, he goes mad, and kills all the other lanterns and the guardians of the universe, taking their power rings and, frustrated with the senselessness of the world is prepared to sacrifice it all to remake the timeline into an idyllic one, only to be stopped by the superheroes who refuse to sacrifice this world, flawed as it may be. Perhaps something can be read into that being the final moment before the continuity change and what I believe to be the Dark Age's end.
1994-2005: The Reconstructive Era
After Zero Hour, while things were still dark for a while, they started getting brighter. A year after Zero Hour was the next big crossover, Underworld Unleashed which features the Lord of Hell Neron trying to make the world seem horrible and miserable and Shazam's pure soul full of hope anyway defeating him. A year after that was the Final Night event which featured a Sun-Eater threatening to consume the Sun only for Parallax Hal Jordan to return and sacrifice his life to stop it, dying a hero. Stories began to become more hopeful. However it was a conflicted era that went back and forth between idealism and cynicism. Identity Crisis came out in this era, retconning the goofy silver age villain Dr. Light into a psychopathic rapist, and making the JLA more morally ambigious. Batman created contingencies to take out all the other JLA members, lethally if need be. Wonder Woman was forced to kill longtime JLA ally Maxwell Lord, turned out to be a villain, to save Superman. These events led up to the end of the period with Infinity Crisis, where the tensions and suspicions between the trinity led to conflict and featured two Superman fighting in relation to the metafictional idealistic Silver Age Morality vs the Modern Pragmatic Morality and eventually teaming up to fight the rogue Pre-Crisis Kryptonian Superboy Prime...Infinity Crisis is a comic that was very clearly very self-aware of the metafiction surrounding the event, which would make sense given the era after.
The continuity had also changed, to a lesser extent compared to Crisis on Infinite Earths. During Zero Parallax has messed with the timeline, causing changes to resolve some of the left over plot holes and contradictions from Crisis on Infinite Earths such as Hawkman's backstory.
2005-2011: The Meta Era/Heroic Era
NGL this is my favorite era. After Infinite Crisis, the Post-Crisis period started becoming really self-aware and self-referential. Trinity was a whole series about how Superman, Batman, and Wonder Woman were an archetypal trinity needed to maintain the DC Unity. In the same year, center of this period was Final Crisis, a major crisis event that references huge swaths of obscure DC lore and cosmology, and is a metafictional story about the nature of evil and the power of stories celebrating heroism rising over the dark age of comics. All the old Silver Age stuff were being re-integrated into comics with things like Barry returning during Final Crisis and Superboy being retconned back into history in 2010. Infinite Crisis also changed continuity some though not as much as COIE because Superboy punched....reality.
This was an age where things became quite optimistic again for a while, the trinity made up after the events of Infinite Crisis and during the events of Trinity, and people began to trust superheroes more after they saved the multiverse in Final Crisis.
Sadly apparently mine is a minority opinion, as sales were low which led to...
New 52/Post-Flashpoint: 2011-2015/2016
Sales weren't good so DC released an event called Flashpoint where Barry Allen goes back in time, disrupts the timeline, fixes it and this appears to have caused a whole bunch of changes. Initially this was meant to be a "soft reboot" meaning some things were still canon but not all.
New 52: 2011-2015
DC Comics relaunched ALL their titles at issue 1, a first for the company. This would continue for exactly 52 issues, although some titles would be canceled and some titles would start during the period so some of the series at the end of the period were not on issue 52 exactly. The New 52 dramatically dropped the power level, made the characters much more inexperienced and younger to try and make them more relatable, made things signifigantly more sexual, and tried a whole bunch of different ideas all basically to attract new readers and appeal to fanservice.
It really didn't work. This is probably the maligned period in DC history. Now that it's over we can all say it had some good series, and it did but at the time people were calling for the heads of the people working at DC. And TBH, I can't really offer much of a defense. I liked a few things in it but like most people, I was not very fond of it.
If you are gonna vs debate the New 52 it's really easy. It's divided up into "waves" less than a year long, 9 waves, meaning you can easily divide it like you would "arcs" of most series. This period ended with Convergence, an event focused around Brainiac, the Pre-Flashpoint Brainiac being revealed to have saved cities from across the retcons and there being a massive arena-styled game from cities from across DC's continuty led by Brainiac's subordinate Telos.
Post-Convergence/DC You: 2015-2016
Another period technically set during the Post-Flashpoint period, Convergence ended with the restoration of the multiverse and the undoing of the collapse of the multiverse during Crisis on Infinite Earths. This didn't affect the main DC Earth at the moment, it just meant that all the other Earths were still there. This started a brief period called "DC You." Due to the massive influx of frustrations at the New 52, DC You was DC basically trying to have its cake and eat it too with the position that now continuity wouldn't be an important policy, and that they would prioritize "stories over canon" with writers being able to write stories anywhere they wanted. The "New 52" branding was dropped but it still technically was set in the Post-Flashpoint continuity.
On a meta level, DC You only really got mixed critical reception and...not the sales they wanted leading to another reboot, or in this case you could call it...an UN-boot.
DC Rebirth: 2016-2020
Early Rebirth 2016-2018:
In 2016 it was revealed that all the Pre-Flashpoint events had indeed happened on the main DC Earth, but that an external force had removed 10 years of memories and events from everyone that were slowly coming back. This would later turn out to be Dr. Manhattan from Watchmen, a metafictional reference to the darkening of the DCU being a result of Watchmen's influence.
DC relaunched all their titles again, resuming the numbering from Pre-Flashpoint and reinstating a lot of things from before the Flashpoint as what one could call a big "mea culpa" for all that had happened. The event got a massively positive reception and it set up what is basically the current continuity, with everything being canon.
Post-Dark Knights: Metal: 2018-2020:
In 2018 Dark Knights: Metal was released involving the Barbatos, the god of the "dark" multiverse, flip side of the regular multiverse trying to invade the main multiverse attempting to use Batman as a conduit after Batman was sent back in time during the events of Final Crisis. In the defeating of Barbatos, the JLA reach and shatter the Source Wall. The Source Wall is an immense deal in DC, being the boundary to imagination and thought, containing the 5, at the time, known "dimensions" of DC. It was discovered by the JLA that in fact that there were other realities beyond the Source Wall and that by opening the Source Wall, they had opened up the potential for things from the higher Sixth Dimension beyond imagination to enter the multiverse.,
Dark Knights: Death Metal: 2020
The final major event up to the present. This is a direct sequel to Dark Knights: Metal and is about the conflict between Crisis Energy which seeks to change things and Anti-Crisis Energy which seeks to maintain things. From the Source emerges a race of super-celestials called The Hands living in the Sixth Dimension, each one creating a multiverse and when finished returning to the Source, but a rogue one called Perpetua which is revealed to be the hand in prior DC Crisis that created the multiverse made a multiverse running on Crisis and Anti-Crisis energy so it would never be finished and instead constantly be fighting so she would not disappear back into the Source. Wonder Woman uses anti-crisis energy to restore everyones memories of every crisis, very clearly making everything in DC history canon and as a giant metafictional statement that DC isn't gonna be using Crisises to try and retcon the past anymore.
Infinite Frontier: 2021
Infinite Frontier is the newest big thing in DC. Wonder Woman was ascended to a goddess state at the ending of Death Metal and IF is basically the Spectre taking Goddess Wonder Woman around showing her the new status of reality after Death Metal and the Future State event, the time in between the two where it was showing possible futures. The big reveal of it, big spoilers
...
Darkseid has returned from his death in Final Crisis, stronger than ever, killed the Quintessence and is now preparing to destroy everything.
So that's the periods of DC Comics to my understanding and how I would divide the verse into "arcs" like most verses.