Every Order Palpatine Has Throughout 'Star Wars' (Besides Order 66)
Order 66 is one of the most well known and devastating moments in the Skywalker saga. As Palpatine's evil machinations come to fruition, the trap laid for the Jedi over the course of several decades is sprung. Order 66 is bloody and brutal. Especially for fans of the animated The Clone Wars, seeing the guardians of peace and justice wiped out by their own troopers is heart wrenching. While this Order was the ultimate goal behind the creation of the clone army, there are several other important Contingency Orders instilled in the Kaminoan-created troopers (in Legends, at least). Every trooper is required to memorize these Orders before they are promoted from cadet. Any clone found to be in violation of these Orders would be accused of treason against the Grand Army of the Republic, stripped of rank, and subject to execution.
Order 4
"In the event of the Supreme Commander (Chancellor) being incapacitated, overall GAR command shall fall to the vice chair of the Senate."
A fairly cut and dry order, Order 4 outlined the chain of command in the event that Palpatine is unable to fulfill his duties. The vice chair of the Senate, Mas Amedda, would assume all his duties, responsibilities, and power. A Chagrian, Amedda is fiercely loyal to anyone who could further his own power, in this case, the Chancellor. Mas Amedda continues to serve Palpatine until the end of the Empire. After the Battle of Jakku, it is Amedda who formally surrenders on behalf of the Empire against New Republic forces.
Order 5
"In the event of the Supreme Chancellor being declared unfit to issue orders...the Chief of the Defense Staff shall assume GAR command and form a strategic cell of senior officers until successor is appointed."
A very similar protocol to Order 4, with the exception of the Chancellor being unfit for service and power falling to the Chief of Defense. This Order is first mentioned in Republic Commando: True Colors, one of the many exceptional novels about the Clone Wars by author Karen Traviss.
Order 37
"Capture of a single wanted individual through the mass arrest and threatened execution of a civilian population. Follow-up directives include scenarios for body disposal of civilian casualties and suppression of communications."
The darkest of the Contingency Orders, Order 37 calls for nothing short of war crimes. It seems surprising that the Republic would implement such a brutal and immoral protocol. However, this order illustrates how far the Republic has fallen by the time of the Clone Wars. Once a beacon of light and hope in the galaxy, the galactic capital of Coruscant becomes riddled with corruption and greed. Many in the Senate would vote for executing Order 37 if it meant protecting their personal wealth and goals.
Order 65
"In the event of either a majority in the Senate declaring the Supreme Chancellor to be unfit to issue orders or the Security Council declaring him to be unfit, GAR commanders shall be authorized to detain the Supreme Chancellor, with lethal force if necessary."
While Order 66 was meant to protect the Republic from traitorous Jedi, Order 65 was the other side of that coin, meant to safeguard the Republic from a corrupt Chancellor. This also demonstrates how corrupted the Senate is by the time Palpatine reveals himself to be a Sith Lord. The Jedi Council could not afford to bring their allegations against the Chancellor before the Senate and try to enact Order 65, as key seats in the Senate are firmly in the Sith Lord's pocket. The Senate would never have passed a resolution to enact Order 65, and could have compromised the Jedi Council's position in the Republic.
Order 151
This "bonus" Order is the first to be given to troopers following the fall of the Republic and the rise of the Galactic Empire. The newly christened Emperor Palpatine hands down Order 151 in secret to his loyal clone troopers. This order is very similar to Order 66, but specifically targeting Darth Vader. Clone troopers, upon receiving this order, would hunt down and eliminate the Dark Lord of the Sith. However, by the time the clone troopers are phased out in favor of stormtroopers, the Contingency Orders, like the Republic, are things of the past.
Source(s): Wookieepedia