Yavin blockade

The Blockade of Yavin was a military action conducted by the Galactic Empire after the destruction of the Death Star in 0 ABY.

History
Darth Vader led a fleet that surrounded the system in order to defeat the Core Group of the Rebel Alliance. The blockade was so extensive, it covered the entire Gordian Reach. Though it was a large blockade, smaller ships could escape, while the large transports and capital ships were prevented from leaving. The blockade was more political than military, because the Empire didn't want the galaxy to know that an enemy was threatening it. Luke Skywalker, Princess Leia Organa, and Han Solo managed to escape the blockade multiple times. Once to the Wheel, to Hoth, Drexel, Aduba III, Akuria II, Keeper's world and other planets. Just before the blockade, Tyber Zann searched the debris of the first Death Star, locating several jettisoned pods that contained secret plans to the Eclipse and other plans. Tyber Zann left the system just after the Imperial fleet arrived.

House of Tagge intrigues
The original commander for the blockade was General Ulric Tagge and was assisted by his family's company, led by Baron Orman Tagge. Several Tagge warships helped take part in the blockade. It was Orman Tagge's goal to gain favor with the Emperor, by creating a rivalry with Darth Vader, and humiliating him. Orman Tagge used his vast resources of TaggeCo to develop weapons to defeat the Alliance at Yavin. The first was a station in the planet of Yavin that carried a turbine to allow fighters through the turbulent atmosphere, called the Achtnak Turbine Station. TIE/ln starfighters used this station as a depot to allow them to maintain a continuous siege of Yavin 4. This station was eventually destroyed by Luke Skywalker. The second attempt used a new freezing bomb weapon, the Omega Frost. Han Solo led a Rebel fleet through an unknown gap of the Imperial fleet. Luke Skywalker managed to destroy the firing mechanism, and the Alliance fleet attacked Orman Tagge's fleet and led to his defeat. After this failure, Vader held Orman and Silas Tagge prisoner, and thus had leverage over Ulric Tagge, who believed his brothers dead, assumed the title Baron Tagge and retired from the military.

Admiral Griff's involvement
At the same time, Darth Vader was being pressured by Imperial commanders to strike, having lost patience in the blockade. A group of Admirals secretly revealed the existence of the Super Star Destroyer being built at Fondor to the Rebels. Luke Skywalker led a team to destroy the new weapon, but failed. Admiral Amise Griff, one of the treasonous admirals, was actually a spy for the Sith Lord. Vader killed the admirals for their betrayal. Vader rewarded Griff by placing him in command of the blockade. Griff launched stunning raids on the Massassi base on Yavin IV. His TIE fighters were slowly winning the battle of attrition. Fortunately for the Rebellion, Princess Leia and a pirate fleet led by Silver Fyre ran the blockade and defeated the TIE fighters. The Empire continued to besiege the base, launching several raids to destroy transports and kill leaders. The Bothan High Command were killed in one attack, while Rebel fighters led by Commander Skywalker defended the transports in another attack.

When the Super Star Destroyer Executor was finished, Vader led a final strike on the base with his new flagship. At the advice of Luke Skywalker to relocate to Hoth, the Alliance evacuated the last of the base, and attempted to delay the arrival of the Super Star Destroyer. The first attempt failed, and its commander, Vrad Dodonna, fled the battle, damaging his own ship to appear he barely escaped. Luke Skywalker caught Vrad from escaping, but did not want to hurt General Dodonna's feelings for his son. Vrad and Luke then volunteered on a mission to use a power gem to weaken the Executor's shields. Vrad, however, left Luke behind to escape on his own and sell the power gem. Attacked by the Executor, Vrad was forced to change course and rammed the ship. As the Executor redirected all power to its forward shields, the Millennium Falcon damaged the ship's rear. Unable to strike the Rebel Base, Darth Vader called upon Admiral Griff at Jovan Station to use the blockade force. Admiral Griff responded by sending a TIE Bomber fleet to destroy the base. However, General Dodonna detonated the temple&mdash;the blast destroyed the bomber fleet. This allowed the last Alliance transport to escape.

Final actions
Despite successfully evacuating the base, the Rebels were still faced with escaping from the Imperial blockade. Rebel-aligned Admiral Ackbar and his Mon Calamari forces attacked the Vallusk Cluster and two other locations along the blockade as a diversion. This allowed a gap in the blockade for the Alliance to escape. Admiral Griff was not fooled, and sent his three Star Destroyers to a nearby star to hide and wait to ambush the Rebel fleet. Luckily, Luke Skywalker discovered the Star Destroyers and warned them. Instead, Princess Leia led the fleet through a stellar flare around the star, with Skywalker guiding them through the Force. Meanwhile, with the repairs complete, Darth Vader and the Executor awaited on the other side of the star to ambush the fleet. Darth Vader had used Griff to draw the Alliance near him, and exhaust them. But the ambitious Griff, foolishly miscalculated a hyperspace leap to catch the Alliance, and his three Star Destroyers collided into the Executor. Admiral Griff was killed, but fortunately for Vader, the Executor's shields protected him from the collision. This event allowed the Alliance to escape. The Alliance finally escaped the Imperial blockade and spent a year relocating to Hoth and building Echo Base.