The territory claimed by Liberland is the largest green-coloured land parcel, marked as "Siga" on the map. Due to differences in the border definitions, the yellow-coloured parts to the east are claimed by both Serbia and Croatia. Croatia asserts that the green parts are part of Serbia, but Serbia does not claim them. This led Jedlička to assert that the green parts have remained unclaimed by both sides.

The flag raising in Gornja Siga was performed by Vít Jedlička and some of his associates on the same day the republic was proclaimed.[1][2] Jedlička is a member of the Czech Party of Free Citizens, which bases its values on the classical liberal ideology.[3]

Jedlička stated that no nation claims the land as its own and he therefore could claim it using the terra nullius doctrine. The border, he argued, was defined in accordance with Croatian and Serbian border claims and did not interfere with any other state's sovereignty.[4] Jedlička said in April 2015 that an official diplomatic note would be sent to both Croatia and Serbia, and later to all other states, with a formal request for international recognition.[4]

On 18 December 2015, Jedlička held an event at which he presented the first provisional government of Liberland and its ministers of finance, foreign affairs, interior and justice as well as two vice presidents.[5]

Croatian authorities have frequently blocked access to the area since the beginning of May 2015.[6][7]

In May 2015, Vít Jedlička and his translator Sven Sambunjak were briefly detained by Croatian police after making an attempt to cross the border. Jedlička spent one night in detention and then was convicted and ordered to pay a fine for illegal crossing of the Croatian border[8] but appealed the verdict. He claimed that there were at least three Liberland citizens inside the area, who came from Switzerland.[9][10][11][12] Later that month, Vít Jedlička was detained again.[13] Initially, reporters were able to enter the area with Jedlička[14] but subsequently they were also denied entry, including journalists from the Serbian public broadcast service Radio Television of Vojvodina,[15] and from the Bosnian newspaper Dnevni avaz.[16]

The detained were from various countries, including the Republic of Ireland, Germany, Denmark, and the United States.[7] Croatian police have continued detaining people, including those that entered the area by boat (via an international waterway).[17][18][19] One of them, Danish activist Ulrik Grøssel Haagensen, was placed in house arrest for 5 days before being sentenced to 15 days of prison, triggering some protests in Denmark.[20][21]

In May 2016, several appeals court decisions from Croatia were published. The court upheld that the crossings from Croatia were illegal, but found the convictions for crossings from Serbia improper. The court said that the lower court committed "a fundamental breach of misdemeanour proceedings" and "essential procedural violations". It further ruled that "the facts were incorrectly and incompletely established [by the prosecutor] which could lead to misapplication of substantive law". A retrial was ordered in 6 of the 7 appeals. The lower court is required to determine the location of the border and the border crossing.[22]

In 2022, the American travel videographer Drew Binsky visited Liberland's "Floating Man" summer festival in Serbia. Together with some other attendants, he made an attempt to enter the area claimed by Liberland, using a boat from the Serbian side of the Danube. The group was intercepted by Croatian police and ordered to return.[23]