One of Capone's first employers and allies was Frankie Yale, who stayed close allies with Capone despite a knife fight that scared Capone's face. The two remained allies until 1928 when Yale was whacked. There's debate over if Capone or a local rival gang assassinated Yale.
Capone began his criminal activities in the Five Points Gang before being accepted into Johnny Torrio's Chicago Outfit most likely in the early 1920s. He quickly rose in the ranks and became Johnny's right-hand-man. On Saturday, January 24, 1925, Johnny was shot by a rival gang but survived the assassination attempt and lucked out when the assassin ran out of bullets when trying to shoot Johnny in the head for a coupe-de-grace. But Johnny's recovery was slow, and he was temporarily imprisoned during this time. Weakened both physically and mentally by these events, Johnny saw his reign as a mob boss ending and so declared Capone as the new Chicago Outfit leader in late 1925.
Although he was never successfully convicted of racketeering charges, Capone's mobster career ended in 1931, when he was indicted and convicted by the federal government for income-tax evasion. He was sent to a series of prisons including Alcatraz, which was the longest and most famous of his sentences.
The Chicago Outfit still exists today but has been overshadowed by common street gangs like The Crips.
The battle begins in an American history museum in Chicago hosting an exhibit about Old West outlaws. Inside, Jesse James, his brother Frank James, and two other gang members are in the Civil War exhibit, breaking the glass exhibits and arming themselves with Colt revolvers and looting some of the Civil War coins. Meanwhile, Al Capone and three of his men drive up to the museum, alerting the James Gang who have finished loading up their newly acquired revolvers. The Capone Gang enter and are suddenly ambushed by Jesse James and his men. Jesse's team score the first kill in the quickdraw showdown.  A hailstorm of bullets ensues as both factions open fire on each other, with a Capone flunky taking out one of Jesse's men out with a Tommy gun.  Amidst the gunfire, Jesse James's other henchman steals a Winchester rifle from one of the cabinets and lays down some suppressing fire while Jesse and Frank retreat further into the museum. Al Capone's men come out of cover and begin chasing them, with Al Capone dusting off his hat and following close behind.
Jesse's rifleman stops in a hallway and cocks the Winchester, shooting one of Capone's two remaining men as he rounds the corner. Hooting with victory, he runs back to Jesse. Frustrated, Capone's other henchman tries to shoot down the outlaw, fruitlessly firing in all directions. Al Capone catches up and the two men begin to run after Jesse James's crew. The third man struggles to catch up, but is stabbed from behind by Frank, who emerges from a dark closet with the Bowie knife. 
Capone and his last co-hort enter an office, where Jesse and his henchman are waiting for them. Jesse shoots Capone's man with the revolver, catching him off guard. Capone quickly ducks for cover behind a desk right before the rifleman finishes the last man on Capone's team with a shot from the Winchester.  The rifleman waits for Capone to make his move, unaware that Capone is pulling the pin from his MK2 "Pineapple" Grenade. He hurls the grenade over the desk and quickly hides again. The rifleman attempts to shoot Capone, but is killed by the explosion before he gets a chance.  Capone gets up and tries to steal one of the revolvers, but Jesse James shoots it out of Capone's hand. Realizing he has been beat, Capone slowly stands up with his hands up in surrender. Jesse James sneers as he pulls the triggers on his revolvers, only to find that both of his guns are out of bullets. Jesse quickly flees while the infuriated Capone pulls off his trench coat and gloves and puts on his brass knuckles, intent on finishing Jesse.
Jesse runs for his life, but is cornered when he winds up at an exhibit for a western jail cell. He turns around to see that Capone has caught up. He tries to pistol whip Capone, but Capone blocks the swing and counters with a punch in the gut with the brass knuckles. Removing his hat, Capone forces Jesse into the mock jail cell and begins to brutally beat Jesse. After kicking James to the floor, Capone draws his Stiletto knife while Jesse gets up with his Bowie knife at hand. Scarface Al goes in for a thrust, but Jesse hooks his hand with the stock of the revolver and stabs Capone at his arm. Enraged, Capone then kicks James as he drops his stiletto, forcing Jesse to also drop his knife. Capone grabs James and holds him against the cell door, continuing to lay into him with the knuckles. Right as he's about to deliver the killing blow, the both of them hear a gun cock. Capone looks up to see Frank James with the Winchester. Frank fires the gun, hitting Capone dead center between the eyes and causing him to stumble backwards onto the prop toilet. Jesse James celebrates the victory after dusting off his hat, then runs off with his brother to steal whatever they can of the museum.
Capone's driver is shown in the fight but never leaves his car. This is similar to the boat driver for the Somali Pirates.
Capone was also called Scarface after a knife fight with mobster Frankie Yale scarred the left side of his face.
The Al Capone Gang is officially known as the Chicago Outfit.
Although not mentioned in the show, Al Capone was 5' 10" and 250lb before his arrest. This makes Capone the heaviest warrior.
2 of Capone's men were armed with Tommy Guns with 50 round drum magazines, the third man was armed with a Tommy Gun with 30 round clip magazines.
This is the only time two warriors of the same team survived the battle.
Capone himself lead his bodyguards for many driveby shootings and murders. He was arrested many times but witnesses were threatened and the charges were dropped.
Several clips from the Mafia vs. Yakuza episode are reused for this episode, including beating a man in an alley with a Baseball Bat and throwing a Molotov Cocktail through a rival business's window. In real life, Capone wanted to join the Mafia but couldn't as he was an Italian-American instead of fully Italian. However the Chicago Outfit were allied with the Mafia.
Once, upon a visit to Florida, Capone found himself surrounded by a group of police officers pointing shotguns at him. He remarked, "Well, I'll be damned. You'd think I was Jesse James."
Capone's favored ride was a green 1928 Cadillac Town Sedan. It had 3,000 pounds of bullet-proof armor beneath the standard body. Its windshield and windows were made of recently developed inch thick bullet proof glass. In total the armor made the car weigh 9,000 pounds. Following the attack on Pearl Harbor, the car was pulled out of storage to shuttle FDR to his speech before Congress, asking a declaration of war against Japan.