BIOGRAPHY
Kelsey Shorr Leigh was an Englishwoman and a schoolteacher, focused on History and English Literature. She once had a relative idyll life with her husband Richard and two young children. 
However, everything changed the night a man broke into their house. The criminal tried to rape her, and Kelsey angered him by trying to fight back. Richard was too scared to do anything to help Kelsey, as the man took a broken bottle and carved a brutal scar across her face, becoming a permanent disfigurement. Richard’s inaction was a breaking point for their marriage, and soon Kelsey was left a single mother to two kids.
The Leighs carried on as best they could until one day Kelsey and her children were eating at a local pub, the Tallymander, when the Avengers got into a pitched fight nearby with the Wrecking Crew. Kelsey saw Hawkeye facing three of the Crew out front and decided to leave the back way 
with her children. Unfortunately, they walked into a second brawl between Captain America and Thunderball. Cap was wounded trying to protect an injured Wasp, and Thunderball moved in for the kill. Kelsey took up Captain America’s shield and used it to defend her children and the fallen heroes from the villain’s wrecking ball. The sheer, magical force of Thunderball’s weapon was transmitted even through the indestructible shield, and Kelsey suffered fatal injuries before She-Hulk arrived to fend off Thunderball.
In the aftermath, the Avengers sought medical treatment for Kelsey. Despite their efforts, it was too late and she died from her wounds. The team was left with Martin and Jenny in their care, trying to console the kids over the loss of their mother. Meanwhile, the spirit of Kelsey Leigh arrived in Avalon, where she was greeting by Brian Braddock and his lady, Meggan, the protectors of England. Her great courage and self-sacrifice made Kelsey a candidate for the power of Captain Britain, like Brian before her. She was given a choice between the Sword of Might and the Amulet of Right… and was warned that her destiny would be guided by this choice. She could receive the power to protect the realm and return to her children, but she could also make a choice that meant never seeing her family again.
Thinking that a necklace would be useless in protecting the realm, Kelsey chose the path of the Sword. She was instantly imbued with the Omniversal power and costume of Captain Britain. 
However, because she chose the path of violence instead of justice, her restored life and newfound strength came with a price. Should she ever reveal herself to Martin and Jenny, Brian said it would be their fate to die painfully and horribly. Kelsey was furious over this turn of events, screaming at her patron even as she was displaced back to Earth, right in the path of Thunderball. He was a worthy target for her rage, but the villain was soon revealed by a fallen glamour as the Black Knight of Morgan le Fay, and the matter was not over.
The new Captain Britain and Scarlet Witch followed Morgan and her Knight back to Otherworld, where the dark sorceress had already taken Brian Braddock hostage. Morgan believed the power of Avalon made Brian the symbol for all of England. Harming him should, in turn, destroy England, freeing the power of Avalon for her to wield. Brian foresaw Morgan’s coming, however, and he transferred his connection to England into Kelsey when he made her Captain Britain. Morgan realized the trick, though, and turned her Knight loose on Kelsey. This time, someone came to help her, as Captain America and the Avengers arrived in Otherworld at her side. With this support, the new Captain Britain struck down Morgan le Fay with her Star Sceptre.
Back on Earth, the Scarlet Witch petitioned for Captain Britain’s new membership in the Avengers. Wanda knew Kelsey’s secret from Otherworld, and helped arrange for Martin, Jenny and their 
grandmother to move into Avengers Mansion as well. The cover story was that the Avengers were acting in honor of Kelsey Leigh’s sacrifice, for Mrs. Shorr likely could not support two children on a pensioner’s income. However, even her fellow Avengers didn’t know Kelsey’s true identity, for fear of that knowledge spreading too wide and reaching her children, leading to the cursed results she was warned to expect. And so, Kelsey Leigh became a super-hero, watching from a distance like a stranger while her children were uprooted and mourned her death. [Avengers (3rd series) #77-81]
Captain Britain was not in the right frame of mind to attend her own funeral (if there even is such a thing). Captain America made a display of naming Kelsey Leigh an honorary Avenger for her 
bravery, and even commissioned a statue of her in the Avengers’ garden for fallen heroes. Already following the path of the Sword, Captain Britain couldn’t hold her tongue over the Avengers’ sanctimonious prattling. As Kelsey Leigh, she was humiliated over being immortalized with that scar on her face, but as Captain Britain she decried how the Avengers’ failure to stop villains like the Wrecking Crew permanently was responsible for the lady’s death. Her speech went a long way towards cluing the other Avengers in on her true identity, but they were called to face the Invaders before much could be done about it. [Avengers (3rd series) #82-84]
And soon, the Avengers fell altogether. An insane Scarlet Witch triggered attack after attack on Avengers Mansion, with Jack of Hearts exploding, a spawn of new Ultrons rising, and She-Hulk going mad. It was perhaps bitter irony that Wanda’s madness came in part from the restored memory of losing her own children. Captain Britain was seriously injured and fell into a coma during the “chaos wave.” [Avengers (1st series) #500-501] She survived, but many did not, and 
the team proved too beaten and weary to carry on. In the aftermath, Kelsey said her good-byes to the Avengers and thanked them for changing her life. [Avengers Finale #1]
[Note: The sudden ending of Kelsey Leigh’s arc brought about by Avengers: Disassembled left a number of dangling threads. The fate and whereabouts of her family after Avengers Mansion was destroyed wasn’t mentioned. No effort was made to continue concealing her identity in this final arc, indicating the Avengers already knew. Also, her scar was missing in Avengers (3rd series) #81, but returned for Avengers Finale #1 onwards. This was apparently only an art error.]
Left alone with her thoughts, Kelsey turned to bitterness. She was still unable to reach out to her children, or even let them know she was alive. When she heard Brian Braddock had returned to the UK from Otherworld, she sought him out. Now calling herself Lionheart, Kelsey wanted revenge on the man she blamed for ruining her life. Her savage attack threatened both Captain Britain and Courtney Ross, who he was with at the time. After striking their car with a propane tank, Kelsey momentarily believed the two dead and wavered on whether her vengeance was worth it. However, that hesitation was lost when a new figure named Albion entered the fray and 
encouraged Lionheart’s vendetta. She could not bring herself to kill Ross in cold blood while Brian and Albion fought, though. Albion counseled her they were at war now, and sacrifices would have to be made. Still, the arrival of the new Excalibur encouraged Lionheart and Albion to flee and confront their hated foe another day. [New Excalibur #4-5]
Lionheart learned that Albion was another chosen Captain who picked the Sword over the Amulet. On his Earth, the War to End all Wars never ended, and generations fought and died in an eternal struggle before he faced Merlyn and Roma. When Albion claimed the Sword of Might (apparently the first example of a potential champion doing so), they tried to take back his power and then abandoned him to his Earth. Albion swore vengeance against the Omniversal guardians for their arrogance and refusal to aid his war-ravaged land further. On Earth-616, he added Lionheart to his Shadow-Captains, former mutants from the Decimation now gifted with Captain Britain Corps-style uniforms and power to serve his ends. [New Excalibur #18]
[Note: Lionheart was erroneously called “Kelsey Kirkland” in the above issue.]
Lionheart and Albion made an alliance with Shadow-X, the dimension-displaced dark counterparts of the original X-Men. Jean Grey attempted to corrupt Lionheart’s mind in their first meeting, making it clear Shadow-X couldn’t be trusted. Albion knew this, and equipped Kelsey with defensive psi-shields before the meeting, which only irked Grey further. The Captains pretended to honor the alliance as Lionheart helped Shadow-X infiltrate Crossmore prison, where their master the Shadow King and his host Dark Xavier were being held. Grey tried to force Lionheart into becoming the Shadow King’s new host, but she was ready for the betrayal. Kelsey was not only further protected against psi-attacks, she attached a collar to Xavier that trapped the Shadow King in his vessel before killing them both. Here, Albion eliminated a potential rival while also creating a distraction for Excalibur. While Braddock’s super-team converged on Crossmore, Albion and the Shadow-Captains conducted their own mission simultaneously while raiding a hidden vault in the UK. He unleashed the power of an unknown scepter, neutralizing all electronic devices and communications throughout the United Kingdom with its spell. [New Excalibur #19-20]
Albion prepared Great Britain for conquest, and dispatched Lionheart to Balmoral to secure the royal family. The Queen must either bend the knee to her conquerors, or be removed as an obstacle. Kelsey began to waiver, as a quest for personal vengeance had snowballed into treason 
and the murder of innocents. Excalibur and Shadow-X made for strange allies as they joined together defending England and the Queen, and they stood in Kelsey’s way. Brian Braddock finally forced her to recognize she was no longer serving her interests, but Albion’s interests alone. Lionheart realized she had gone too far and ended the fight with the royal family’s protectors. [New Excalibur #21]
Back in London, Lionheart tried to reason with the other Shadow-Captains, but they remained loyal to Albion. Captain Britain and Albion fought to a standstill, but with that distraction the scepter was recovered from the vault and its magic was reversed, restoring power to the United Kingdom. Albion was imprisoned, and later taken before the Captain Britain Corps for judgment. The British government acknowledged Lionheart’s change of heart and chose not to pursue charges against her. However, she was now in their custody and in their service for the foreseeable future.
Brian Braddock and Pete Wisdom met with Kelsey in the aftermath and brought her the opportunity for both sides to make amends for their failures. The Crown made special effort to bring Martin, Jenny and Kelsey’s mother to Parliament for a meeting. At Brian’s encouragement, Kelsey Leigh removed her mask and shared her identity with her family, with no repercussions. The truth was massaged, and Kelsey’s children were told she was on a secret mission for the 
Crown and couldn’t reveal her identity to them until now. No explanation was given for why Lionheart and her family were no longer cursed to remain apart. Perhaps the simplest reason is that the path of Might required a sacrifice from those who followed it. By turning back towards the path of Right when she opposed Albion, Lionheart’s power no longer came with that stipulation. [New Excalibur #23-24]
Lionheart’s recent activities are unknown. The Sword of Might has changed hands, with Brian Braddock passing the Amulet and role of Captain Britain to his sister Betsy, then becoming Captain Avalon through the power of the Sword. How this might have affected Kelsey and her powers is uncertain. [Excalibur (4th series) #6, 13]