Universal Act of Loyalty
In favor of self-determination, the militant group Rift Republican Army occupied a political prison, Efrimal Long Maximum Security Prison, in the spring of 2573. In response, First Consul of the Republic Gregory Amaris ordered the 5th Amaris Fusiliers and the Amaris Republican Guards to suppress the uprising. When Amaris's troops were fought off, Gregory instituted martial law and ordered the prison razed, killing all of the terrorists (and many political prisoners).
Unsatisfied with just putting the uprising down, Amaris then issued the Universal Act of Loyalty. The Act forced all citizens of the Rim Worlds Republic to swear a binding oath to the Republic and the Star League. Furthermore, the Act removed all local judicial oversight in favor of Star League courts without appeal. Republican citizens that refused to take the oath were branded as traitors, losing all property and legal rights within the Republic.
More than 70% of Republican citizens took the oath, but only under duress, with the worlds of Somerset and Lackhove refusing the oath entirely. Somerset was embargoed until the populace, clansmen of Terran Scottish descent, reconsidered, and Lackhove was pacified by deployment of the 3rd Amaris Dragoons in 2574. 
- The Periphery, p. 24 "History - Star League Era - Rebellion in the Rim"
- Historical: Reunification War, p. 127