(This is all from the manga, not the anime series).

Captain Morgan Arc is the first story arc in the popular Japanese manga/anime series, One Piece. This arc is actually three stories in one. The first is an origin story of how Monkey D. Luffy gained his powers and tells us his driving force to become a pirate. The second story is his meeting with Coby and helping him escape from a female pirate named Aliva. The final story has our hero trying to get the pirate hunter, Zolo, to join his crew while dealing with the madman marine Captain Morgan.

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This saga starts off with a flasback Gold D. Roger was about to get excuted, before he dies he tells the crowds to go out and search for his treasure. With that he sparked the Golden age of pirates; countless pirates rise their flags and sets off to find One Piece.

Retrieved from "http://en.wikipedia.org/wiki/East_Blue_Saga"

We then move 12 years later to Fuschia Village where we immendently meet Luffy (age 7 at time), who foolishly tries to prove his worth to some pirates by stabbing himself in the cheek (which causes a cross shaped scar). Afterwards we get a more formal introduction to Luffy and his idol, Red-Hair Shanks, while his crew enjoy themselves in a bar owned by Luffy's friend, Makino. Shank's crew has used the village as a base of operation for a year of which during that time Luffy has taken a appreciation to the pirate life and tries to talk Shanks into taking him with on their next departure. But Shanks continually refuses as it too dangerous and instead teases Luffy on his inability to swim.

The mood shifts when mountain bandits enter the bar and their leader, Higuma, demands some rum. Makino tell him that the pirates had already finished off all the rum, though Shanks offers the last remaining bottle as an apology. Higuma smashes it over his head and insults him for being a pirate. Shanks ignores Higuma and starts to clean up the mess. This only serves to anger Higuma and causes him to break more bottles. With one final insult, Higuma and his bandits leave. After they are gone, Shanks and his crew laugh at what had just occurred, though Luffy thinks otherwise. He chides Shanks because he didn't fight back and then starts to leave. When Shanks grabs Luffy's arm to stop him, it suddenly stretches! That's when one of the crew members realizes that a fruit that was kept in a chest on the bar is gone. It doesn't take them long to figure out that Luffy had eaten it. Shanks then reveals the cause for panic: Luffy had eaten a Devil Fruit that will cause him to never be able to swim again!

The next day and Luffy starts to see an upside in eating the fruit. He begins to show off his rubber powers to some of the villagers, much to the chagrin of the Mayor of the village who doesn't like the idea of Luffy becoming a pirate. Later, Luffy visits Makino and once again expresses his disappointment at Shanks not fighting back the day before. Next we see Higuma and his bandits enter the bar.

The story shifts ahead a bit when Makino runs to the mayor for help becase Luffy had upset the bandits and they were beating him up. After couple of more poundings, Higuma goes to finish Luffy off. The mayor tries to apologize for Luffy's action and offers money for his safety. But Higuma refuses and proceeds to kill Luffy anyway. Shanks returns and demands he let Luffy go. Higuma laughs at Shanks and sends his men to kill him as well. Instead, Shanks' first mate easily takes care of Higuma's thugs. When Shanks again demands that he let Luffy go, Higuma throws a smoke bomb, grabs Luffy, and escapes. Shanks starts panicking, but his first mate notices something...

Higuma sails a boat away from the town claiming a perfect getaway because no one suspects a bandit would flee to the ocean. Far from land, Higuma throws Luffy into the water and (true to the myth of the devil fruit), Luffy can't swim. A flashback shows us that when Higuma reentered the bar, he immedently started bad mouthing Shank, to which Luffy takes offense and screams for them to take back their words. Back in the present, Higuma laughs at Luffy's struggle but fails to notice the giant sea monster creeping up on him - until it is too late and he is eaten in one bite. The monster then sets his sights on Luffy, but Shanks pulls him away just in time and, wih a very menacing expression on his face, tells the sea monster to leave. The monster leaves and Shanks tries to calm down a sobbing Luffy. Luffy points out that his left arm has been chomped off. Shanks tells him its just a small price to pay for saving him.

Some time later, Shank's crew prepares to leave the village for the last time, and Luffy comes to say his goodbye. When asked if he is disappointed, Luffy replies he is, but won't ask to join and that he will be a pirate on his own. Shanks teases him again and Luffy screams that he will be a better pirate than him - that he will be the king of pirates. Upon hearing this, Shanks gives Luffy his favorite straw hat and make him promise that he will return it someday when they meet again. Afterwards, Shanks and his crew leave the village.

Ten years pass and Luffy, now a teenager (17), is old enough to leave on his own. As Luffy sails away from his village, he runs into the sea monster again. This time, Luffy is ready and punches the monster with a Gum Gum Pistol, instantly knocking it out. Luffy once again reproclaims he'll be the king of pirates!

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The next act in the arc finds Luffy being sucked into a whirlpool but rescued by a pirate crew when they find him in a barrel (which he jumped into at the last second). Their captain, a ugly and fat woman named Aliva, barges in after their discovery. Thinking that their drinking behind her back. But the crewmates put the blame on their cabin boy, Coby.

Meanwhile in some woods not far from the ship, Luffy gets aquinted with say cabin boy who turns out to be quite the coward and only became a cabin boy because he got on the wrong ship while out fishing and it was the only way to spare his life. Coby also reveals he wants to be a marine but feel this goal is out of his reach. However when Luffy tells Coby of his dream and his willingness to do it or die trying, Coby starts to get insipired. Which turns out to be good timing as Aliva finds the two and barks at Coby to say who the prettiest person in the world (something she makes all her crew do). At first Coby starts to do as told, but remembering Luffy's words, he blurts out thats Aliva's the uglist hag in the sea!

This, of course, angers Alvia and she goes to kill Coby with her iron mace (her signature weapon). Luffy pushes him back and takes the blow, taking no damage as his rubber body absorbs the impact. He then retailiates by hitting Aliva with a Gum Gum Pistol, knocking her out with one punch. He then demands to the rest of her crew to give Coby a dingy so he can fulfil his dream of joining the marines (Navy in the english anime).

The crew does so and the two sail off with Luffy wondering if he can get a famed pirate hunter named Roranoa Zolo (Zoro) to join his crew though Coby thinks it'll never happen.

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