Cavlan was first established as the Kingdom of Abrus on November 11, 2015 with a monarchy by Sean Cavanaugh. On January 14 of the following year, Cavanaugh decided to proclaim the nation as a commonwealth realm of the United Kingdom and abdicated the throne, and merged the monarchy with the monarchy of the United Kingdom, headed by Queen Elizabeth II who was then known as the official Monarch of Abrus. At the time, the flag and coat of arms of Abrus were created. The flag represented a variation of the Union Flag, and presented the commonwealth's coat of arms. Cavanaugh became the Prime Minister of the nation. however, on March 3, 2016, during a session of parliament, it was decided that the monarchy be returned to it's original state, where a new monarch was named, and the Government as a British Commonwealth Realm, ceased to exist. Then on September 12, 2016, the Prime Minister called for a 'Government Reset' on the slow and non-functioning government. After this period of time, the Monarchy was dissolved and the nation was re-established as a republic with a constitutional presidential system. This new republican government has been said to resemble that of the United States government in certain areas. On January 7 through multiple debates between the legislature speaker and the President, the Council of Abrus decided to dissolve the entirety of the nation of Abrus. It wasn't until January 14 that the vote in the council came to a conclusion, and after a few weeks of battle between the Council and the President, the nation was dissolved by a unanimous vote, where then, the Government of Abrus ceased operations, and the nation ceased to exist completely.
After Abrus ceased to exist in January 2017, the former President, who strongly opposed the dissolution of the state, established a new independent nation, which he sought to model after the United Kingdom. Cavanaugh established the Kingdom of New Britain on 23 January 2017, as a continuation of the Republic of Abrus. Cavanaugh, who named himself King, eventually changed the name of New Britain to Abrus to solidify its purpose to being a continuation of the former nation. After New Britain was established in January 2017, the King at the time decided the Government became too inactive again, and formed a new government which he thought would serve as an active nation in the micronational community, and would no longer face an inactive government. The provisional government of Cavlan was the first to come out of the wreckage. With a Head of Operations in place, government types and how the government would be run was officially put into plan, and afterwards The Republic of Abrus was established on 2 February 2018. Cavanaugh, former King of Abrus, and Head of Operations of the Provisional Government of Cavlan, declared himself as ruling dictator of the Republic of Abrus, which actually remained until the dissolution in June 2018.
After the dissolution of the dictatorship, Cavanaugh started planning his next nation, and came up with the idea of a new monarchy, under a completely new name; Cavlan. He quickly wrote up a Declaration of Independence, and established the current Holy Empire of Cavlan, which reflects his religion as a devout Roman Catholic.