Let's start with Alan Scott and his history. He pretty much set the stage for Green Lanterns and others to come after him. Also I thought it would be nice to pay homage to his first issue.
Our Thousands of years ago, a mystical "green flame" fell to Earth in ancient China as a meteor. A voice in the flame predicted that it would act three times: once to bring death, once to bring life, and once to bring power. For the first prophecy, a lamp-maker crafted the green metal of the meteor into a lamp. In fear and as punishment for what they thought sacrilege, the local villagers killed him, only to be destroyed by a sudden burst of the green flame. For the second, in modern times, the lamp came into the hands of a patient of a mental institution who fashioned the lamp into a modern lantern. The green flame restored him to sanity and gave him a new life. For the third, by 1940, after having already fulfilled the first two-thirds of this prophecy, the lantern fashioned from the meteoric metal fell into the hands of Alan Scott, a young railroad engineer. Following a railroad bridge collapse, the flame instructs Scott in how to fashion a ring from its metal, to give him fantastic powers as the superhero Green Lantern. He adopts a colorful costume of red, purple, yellow, and brown, setting himself apart from his successors, who wear the standard green. He becomes a crimefighter in his first adventure, defeating the crooks who caused the accident. He also discovers his powers' weakness to wood when he is bludgeoned with a club. Alan is a founding member of the Justice Society of America, and is its second chairman.
Scott uses his ring to fly, walk through solid objects by "moving through the fourth dimension" paralyze or blind people temporarily, hypnotize them, create rays of energy, melt metal as with a blowtorch, and cause dangerous objects to glow, among other things. It could also allow him and others to time travel. Occasionally, he uses it to read minds or create solid objects and force fields in the manner usually associated with fellow Green Lantern Hal Jordan. His ring could protect him against any object made of metal, but would not protect him against any wood- or plant-based objects. This was said to be because the green flame was an incarnation of the strength of "green, growing things".
During the 1940s, Green Lantern seemed to alternate between serious adventure, particularly when Solomon Grundy, his nemesis, appeared and light comedy, usually involving his sidekick, Doiby Dickles. Toward the end of his Golden Age adventures, he was reduced to the role of a sidekick to Streak the Wonder Dog, a heroic canine cut from the mold of Rin-Tin-Tin and Lassie.
A part of Scott's early history is filled out with retroactive continuity. All-Star Squadron Annual #3 states that the JSA fought a being named Ian Karkull, who imbued them with energy that retarded their aging. This allowed Scott and several other members, as well as their spouses, to remain active into the late 20th century without infirmity. The events of that incident also led Scott to take a leave of absence from the JSA, explaining why the character vanished from the roster for a time.
Scott was a member of the Justice Society of America in 1951 when the team was investigated by the "Joint Congressional Un-American Activities Committee," a fictional organization based on the real-life House Un-American Activities Committee. They were accused of possible communist sympathies and asked to reveal their identities. The members declined the offer, and many of the members retired in the 1950s.
The team re-forms in the 1960s with Scott as a member, though little is known of their adventures during this time, save for stories about their team-ups with the Justice League of America, the parallel world Earth-One, and cross-universe adventures Scott shares with Earth-One's Green Lantern, Hal Jordan.
From the late 1940s to the 1970s, Scott runs the Gotham Broadcasting Company (GBC), which ends up ruined by creditors. After this, the Psycho Pirate temporarily drives Alan mad and the rest of the JSA help him recover. Jay Garrick helps him start a new career as a scientist and he eventually regains control of the GBC, which he continues to run. It was eventually revealed that in the late 1960s that Scott marries the woman with the dual identity Rose and Thorn. The two have a pair of children who would grow up to become the superheroes Jade and Obsidian of the team Infinity, Inc..
In the 1980s, Scott married his reformed former nemesis, Molly Mayne, also known as The Harlequin, reconciling with his son and daughter.
The Last Days of the Justice Society of America Special (1986) one-shot tells how Adolf Hitler caused a massive wave of destructive energy to erupt over the post-Crisis Earth in 1945. Scott and the JSA, fresh from burying their Earth-Two comrades Robin and Huntress, enter into a limbo dimension in order to fight an eternally recurring Ragnarok.
Through the machinations of Waverider, the JSA teammates are able to leave limbo and begin living in the post-Crisis Earth they had fought to save. The mini-series is followed by Justice Society of America (1992–1993), which shows how Alan Scott adjusts to his new world. In the short-lived series, the JSA fight the newest incarnation of the Ultra-Humanite as well as Pol St. Germain and Kulak the Sorcerer. Scott reconnects with his wife and children, stating in issue #1 that Molly "is pretty much handling things at the company..." and that Jade and Obsidian "... are fine off doing their own thing in Hollywood. Not too interested in being super-heroes." The series ends with issue #10, not with the team disbanding, but with the members gathering together at their first formal meeting after returning home.
Alan follows Guy Gardner and a small group of heroes to investigate a mysterious distress from Oa, only to be defeated by Hal Jordan, who now calls himself Parallax, having been driven mad after the destruction of his home, Coast City. After the confrontation, Alan discovers that an artist, Kyle Rayner, inherits the remaining Green Lantern ring. After meeting the young hero, he informs him of the situations with Jordan and the Green Lantern Corps. During the Zero Hour event, Alan witnesses the villain Extant incapacitate and kill several of his JSA teammates. After suffering defeat by the villain, Alan gives Kyle his original ring, passing the name "Green Lantern" to him. Alan's ring was later destroyed by Parallax.
For a time, the Starheart became part of Scott's body and he adopts the name Sentinel, becoming a founding member of a new JSA. Thanks to the rejuvenative properties of the Starheart, Scott's physical body is again temporarily revitalized so that he resembles a man in his 30s or early 40s. This drives his wife Molly, who has not been affected, to sell her soul to the demon Neron in exchange for youth. Alan enters the demonic realm, with help from entities such as the Phantom Stranger and Zatanna, and, with Kyle Rayner's aid, manages to win Molly's soul back, reuniting Molly's essence with her souless being.
He has since been physically altered again so that he more closely resembles his true chronological age. He returns to using the name "Green Lantern" during the JSA's battle with Mordru. He continues to fight crime in his original costumed identity, rebuilding a ring and serving as an elder statesman to the Justice Society of America and to the superhero community in general.
In Green Lantern: Rebirth, Alan and his daughter Jade, assist the surviving members of the Green Lantern Corps, Hal Jordan, who had been possessed by the ancient fear entity Parallax, John Stewart, Guy Gardner, Kyle Rayner, and Kilowog, in defeating the Parallax-possessed Ganthet. Alan is increasingly weakened due to Parallax' failed attempts to control him as it did with Stewart, Gardner, and Kilowog, so it decides to kill him instead. However, Jordan, with the aid of The Spectre, breaks free from Parallax' influence, and saves Alan from the fear entity.
During the Rann-Thanagar War, Kyle Rayner's power ring revealed that Scott is an honorary member of the Green Lantern Corps.During the Infinite Crisis, Scott and his daughter Jade, along with many others, travel with Donna Troy to the center of the universe to save it from Alexander Luthor, Jr.. Though they manage to succeed in saving the universe, Jade dies on this mission. A year later, Scott is still active and relatively youthful compared to his true age, but now wears an eyepatch having lost his eye in a Zeta beam transporter accident while returning from space. Though Scott loses his daughter, he tells Kyle Rayner that he still has family both through relations and close friendships, among which he counts Kyle.
Alan Scott wearing the armor of his Earth-22 counterpart.
Week 4 of the 52 maxi-series reveals that Scott lost his left eye during a period when he and several other superheroes were declared missing approximately 11 months prior to the events of Checkmate #1. The Zeta Beam that Adam Strange had hoped to use for teleporting the heroes away from the time-space ripple caused by Alexander Luthor, Jr.'s actions was splintered by the ripple itself, mutilating the heroes in various ways.
In Week 5, Alan goes to the wife and daughter of Animal Man to tell them that Animal Man is missing in space. This gives Ellen Baker more hope that her husband is alive.
In Week 29, Alan, Wildcat, and Jay Garrick (Flash) are the only members of the JSA present on Thanksgiving. They talk about the other members of the JSA and about the new Infinity Inc., which is a new version of a team of which Alan's daughter, Jade, was a member.
After being put into a comatose state during an attack by the Gentleman Ghost, Alan envisions Jade, who tells him goodbye and grants him another portion of her green energy. His missing eye is replaced by a green glowing orb that, due to its mystical origins and connection to Jade, allows him to track astral and mystical energy forms such as ghosts.
During the missing year, Scott has joined Checkmate at the rank of White King, with his JSA teammate Mister Terrific as his Bishop. Scott soon finds himself in a moral conflict with Black Queen Sasha Bordeaux over the violent nature of Checkmate, particularly after Bordeaux and her team slaughter dozens of Kobra operatives during a raid on a facility. Bordeaux contends that the ends justify the means, while Scott adheres to the principle that heroes should not kill unless absolutely necessary. Bordeaux responds by suggesting that Scott resign. Concurrent with this internal conflict, Scott and the White Queen (Amanda Waller) try to keep the organization from being discontinued by political forces.
After the rise of the being Gog, Alan Scott allies with the Justice Society members that oppose Gog's simplistic view of the world. However, after encountering a Justice Society from an alternate universe in which his daughter Jade is still alive, he considers asking the seemingly all powerful being to raise his daughter from the dead. Later, Sandman learns that Gog is rooting himself into the Earth, and if he remains for one more day, the Earth will no longer be able to survive without him. The rest of the JSA arrive to kill Gog by separating his head from the Earth, which is the only way to save the planet. The Society members ally with Gog in an attempt to protect him until they see him attempt to attack a Society member. All of Gog's followers, including Magog, turn on him, causing Gog's blessing on them to be undone. The JSA are able to topple Gog and send him to the Source Wall, but Alan is unable to see his daughter.
In the Final Crisis storyline, Alan led a resistance against Darkseid's forces as one of the superheroes responding to Article X. In Final Crisis #5, he is shown defending Checkmate's Switzerland HQ from the Justifiers. Though Donna Troy tries to place the Justifier helmet on him, Hawkman saves him.
In the Blackest Night crossover, Alan and the rest of the JSA battle the reanimated Kal-L and Black Lantern versions of dead Justice Society members. After Jakeem Thunder is knocked out, Alan is one of the heroes who adds his powers into a "Black Lantern Bomb" designed to mimic Jakeem's Thunderbolt abilities, destroying all of the Black Lanterns in New York. In the final battle of the event, his daughter Jade is resurrected by the power of white light.
In the beginning of the Brightest Day crossover event, Alan lies in the arms of Obsidian, convulsing and writhing as a green light pours from his body. His body possessed, Alan flies off with his JSA teammates in hot pursuit, eventually led the team to Germany. The JSA meet up with Batman's new Justice League and find that Jade, who had been staying on Oa since her resurrection, has returned to Earth inside a green meteor, later revealed to be the legendary Starheart that gave Alan his powers. Sebastian Faust tells the two teams that the Starheart has been gradually taking control of people on Earth for quite some time. Now that it is on Earth, it is growing more powerful and driving metahumans all over the world insane. Jade states that the Starheart captured her in space and purposely brought her to Earth to find Alan and that it is her fault that her father is now in danger. Just then, Alan awakens and his costume transforms into a suit of armor identical to the one he wears in Kingdom Come, and he then tells the assembled heroes that he intends on destroying the world.
Starman is sent into space to search for Alan, and finds that Alan has constructed a massive fortress on the surface of the moon. Before Starman can warn the others, Alan appears in front of him and tears his gem, the source of his abilities, from his chest, thus rendering him powerless. The Starheart uses its influence to corrupt various metahumans with magical or elemental abilities, which creates chaos across the globe. Realizing that the heroes must defeat Alan in order to end the chaos, Batman recruits Miss Martian to get a mental lock on Starman, which, in turn, provides the Justice League with Alan's location. Batman then assembles a small strikeforce consisting of himself, Jade, Hourman, Donna Troy, Jesse Quick, and Mr. America, all of whom have a low chance of being possessed by the Starheart. Mister Miracle arrives and informs the team that Alan has most likely installed Fourth World defenses in his base and offers to use his knowledge of such technology to guide them through the fortress. When they finally find him, Jade uses her powers to restore Alan to normal. With his sanity restored, Alan chooses to allow the Emerald City he created on the moon to stay, and the city becomes populated by various magical creatures from throughout the DCU.
After the events of the Brightest Day, Alan and the rest of the JSA travel to the city of Monument Point, which has been attacked by a superpowered terrorist named Scythe. Just before being defeated, Scythe snaps Alan's neck. In the subsequent story, it is revealed that Scythe is the product of Nazi genetic engineering, and that Alan and Jay had been tasked by the president with killing the experiment back when he was in infancy during World War 2. The two heroes could not agree on a course of action, and, as a result, Scythe was allowed to live. Doctor Mid-Nite discovers that the injuries Alan sustained have rendered him paralyzed, and that any attempt to heal himself could break his constant concentration, which could result in the Starheart once again regaining control of his body.
Jade visits her bed-ridden father in the Emerald City, and offers to use her abilities to help him walk again. Alan declines his daughter's offer, reasoning that if the Starheart were to once again take over his body, it could result in the deaths of everyone in the city. Eclipso attacks the city, which results in Jesse Quick having to get Alan to safety.
Later, the JSA try to take down the villain D'arken who has broken free from imprisonment beneath Monument Point and absorbed the powers of JSA members, but D'arken is too powerful. Due to this only non-superpowered and magical members fight D'arken. The JSA tells Alan that unleashing the Starheart is the only way to destroy D'arken. However, after releasing the Starheart energies, Alan's body begins to incinerate. Afterwards, the JSA attend a funeral for Alan, whom they believe to be dead.
I'm not going into the New 52 series and how they portray him. To me kind of a let down to a great character. Tomorrow or when I get the chance I'll do Hal Jordan. As you can tell Alan Scott lived an exciting life and would also make a great movie just by himself if anything.